Monday, August 6, 2012

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Wednesday, March 28, 2012

Susan Boyle storms the stage once again in the musical of her life

"She was sensational," said Cathy Garraway, a 49-year-old from Sydney.

"It was worth coming half way around the world to see her tonight."

It is three years since Boyle, a devout Catholic, single and living on welfare in the small village of Blackburn, near the Scottish capital Edinburgh, became an overnight star.

It started when footage of her audition for a British television talent show went viral on the Internet.

In the video, the audience and the judges snigger as Boyle, looking dishevelled and more than a little eccentric steps on to the stage.

Then she opens her mouth to sing "I Dreamed A Dream", the hit from "Les Miserables" -- and that was when her life changed.

The footage has since received about 500 million hits on YouTube, according to the musical's producers. And she has gone on to record three albums that have sold more than 16 million copies worldwide.

The new musical is based on Boyle's autobiography, "The Woman I was Born to Be". It follows her from birth, when she was deprived of oxygen, through school when she was bullied for her learning difficulties, to the years spent caring for her mother.

The scene of her breakthrough moment at the audition had the theatre audience cheering and whooping. But they fell quiet as the tale turned to the intrusion of the press and her near-breakdown when she lost the talent show final.

The story is told as if Boyle is narrating it, with her memories revealed like dreams, full of laughter, dancing, music and the love of her large family, as well as heartache at the deaths of her beloved parents and sister.

"I felt that the world hadn't really heard Susan's voice," said co-writer and actress Elaine C. Smith, who Boyle personally chose to play the role.

Smith describes the singer's life as a "fairytale" but told AFP: "I didn't want it to be a sugary-sweet story.

"What fascinated me was that ordinary woman, and what she'd gone through in her life.

"It is a very delicate balance that you play the truth and you play it honestly, and there is fun in the show but there is also great pathos."

The singer approved the script, which is interspersed with hits from her albums and classic songs she associates with key moments in her life.

But she has yet to watch the musical in full, finding it too painful, Smith said.

Boyle remains mentally fragile, although there was little sign of nerves when she took to the stage Tuesday, sending the audience into a frenzy of delight.

"It just took your heart away," said 79-year-old Jeanette Mole.

After a week in Newcastle, the musical goes on a tour of Britain, after which the producers hope to take it to other parts of Europe, to Canada, the United States and Australia -- although many of Boyle's fans couldn't wait that long.

Maire Byrne, a white-haired 70-year-old from Dublin who was wearing an "I Love SuBo t-shirt", was among about 100 international fans who met online and arranged to come to Newcastle together to see the show.

"It was beautifully done -- this is what she wants the world to know about her," Byrne told AFP.

Meg Neiderer, a 52-year-old from Pennsylvania, added: "It's not just her music, her voice -- her story touches people. I can relate to her."

Smith echoed this, saying: "For 20 years we've been living in a completely celebrity-obsessed culture, where if you're not tall, thin, blonde and gorgeous, particularly as a woman, you don't count.

"Susan has sort of put a bomb under that."
Susan Boyle takes to stage in new musical of her life
03/28/2012 Susan Boyle made a triumphant return to the stage on Tuesday at the premiere of a musical charting her rise from humble church volunteer to global superstar.

Susan Boyle made a triumphant return to the stage on Tuesday at the premiere of a musical charting her rise from humble church volunteer to global superstar.

Wearing a glittering red dress, the 50-year-old received several standing ovations as she sang her signature tune, "I Dreamed A Dream", at the opening night of the musical of the same name in Newcastle.

"We love you," shouted out a member of the audience.

James Cameron hits on airwaves with 'Titanic' 3D launch

Cameron dived the wreck 12 times before filming the original, saying it "had a huge impact" on the end result.

"We shot the real wreck -- we didn't just build models of it," he explained.

He said he had told set-builders: "It's got to be exactly like you went back in a time machine and you were on the deck of the Titanic."

The director of smash-hit sci-fi adventure "Avatar" completed his dive of the Mariana Trench, about 200 miles southwest of the Pacific island of Guam, on Sunday morning local time, and revealed it had given him fresh inspiration.

"My interest in things like 'Avatar' -- creating new worlds -- all comes from my curiosity about our world, right here. Every bit of diving I've done feeds into the films that I've made.
03/28/2012 "Titanic" director James Cameron hit the red carpet in London for the launch of the Oscar-winning film's 3D version, as the 100th anniversary of the legendary ship's sinking approaches.

"Titanic" director James Cameron hit the red carpet in London for the launch of the Oscar-winning film's 3D version, as the 100th anniversary of the legendary ship's sinking approaches.

The US filmmaker jetted into the British capital on Tuesday, fresh from his seven-mile (11.2 kilometre) submarine dive to the bottom of the Mariana Trench, the ocean's deepest point.

He was joined on the red carpet by the film's British star Kate Winslet and US actor Billy Zane for the premiere at the Royal Albert Hall.

"The 3D enriches all of Titanic's most thrilling moments and its most emotional moments," Cameron said on the red carpet.

"More than ever, you feel you're right there going through all the jeopardy that Jack and Rose go through," he added, referring to the film's two main characters, played by Winslet and Leonardo DiCaprio.
In "Titanic", Winslet played socialite Rose DeWitt Bukater alongside DiCaprio as male lead Jack Dawson, in a dramatisation of the real-life maritime disaster that claimed more than 1,000 lives.

The biggest, most ambitious ship of the age hit an iceberg on its maiden voyage across the Atlantic Ocean from Southampton to New York, sinking on April 15, 1912.

The new release comes 15 years after the original. The film entered into movie history when it picked up 11 Oscars.

"It is a long time ago and it also feels like yesterday," Winslet told Sky News. "It completely changed my life and it gave me the opportunity to make creative choices.

"It's really great to celebrate it all over again. It's a very different experience, you really do feel as though you're on the boat, the water rushing round you," she added.

The Oscar-winning actress admitted that viewing her younger self would be "weird".

"It is like being forced to go through a photo album of your former self for three and a half hours solidly.

"I haven't seen the whole film in a very long time, I've seen little pieces of it, but it's a whole different me and we look much younger and our acting was different, hopefully not as good as now."

DiCaprio had been unable to attend the event because of work commitments, Winslet said.

Friday, March 19, 2010

nigerian ports authority

ACKNOWLEDGEMENT…………………………………………………………….……..4

PREFACE………………………………………………………………………………......5

ABSTRACT……………………………………………………………………….………...6

COMPANY’ PROFILE…………………………………………………….……………….7

CHAPTER ONE

GENERAL SAFETY……………………………………………..…………………….8

CHAPTER TWO

LOGGING WHILE DRILLING (LWD)………………………………………………..15

CHAPTER THREE

MEASUREMENT WHILE DRILLING(MWD)………………………………..………20

CHAPTER FOUR

DIRECTIONAL DRILLING(DD)………………………………………………………25

CHAPTER FIVE

RIG COMPONENT…………………………………………………………………....29

CONCLUSION ……………………………………………………………………………..34

REFERENCES……………………………………………………………………………..35









ABSTRACT

I did my (Six Months) Industrial Training at Drillog Petro-Dynamics Limited in partial fulfillment for the award of a Bachelor’s degree in petroleum engineering. The (MWD) Engineers really helped me to know the practical applications of most theories studied in school.

This report therefore, only gives an insight into the training, exposures and experience gained during my attachment with the Safety department, Measuring While Drilling (MWD), Logging While Drilling Department, Gyro department, Workshop of PDL.






































COMPANY’S PROFILE

In 1990, DRILLOG PETRO-DYNAMICS LTD. was established by a blend of patriotic, dedicated and experienced oilfield specialists and successful industrialists. The oilfield specialists had worked in multinational oil companies.
As at May 1998, Drillog Petro-Dynamics Limited had successfully done 61 directional Drilling jobs for Shell, Snepco, Consolidated oil, Chevron, up to 45 steer able directional drilling and 4 horizontal directional drilling wells. In addition, 25 magnetic multishot surveys, 4 Gyroscopic and 13 Electronic multishot surveys, 59 Surface Read-Out Gyro Survey and many other jobs were successfully handled within nearly Eight Years of existence.
DRILLOG PETRO-DYNAMICS LTD has very strong technical support agreement with DRILLEX SYSTEM INC. USA and GYRODATA (UK) LIMITED and a retinue of the best technology and detailed training, Drillog Petro-Dynamics Ltd maintains a clear lead in service quality. It sticks to strict adherence to quality assurance and quality control procedure, both in field performance and technical maintenance.
Drillog Petro-Dynamics limited is proactive and future conscious hence it’s huge investment in a maintenance workshop with modern tool handling equipment.
This couples with a stock of new and most modern down hole motors, measurement while drilling equipment and other equipment. This gave PDL an edge over its competitors.
Rules and regulation governing the condition of services of staff was initiated to improve work efficiencies, such rules are procedures for maintenance ,safety, visitors, vendors,
appointment, criteria for assessment, confirmation, designation and other employment process.














CHAPTER ONE

GENERAL SAFETY

HOUSEKEEPING:
You will be responsible for housekeeping in your work area in order to eliminate hazards, keep your workplace tidy.
Floors, steps, stairs and walkways will be kept clean and free from slippery substances, tripping hazards or other obstructions to the best extent possible.
Cargo handling materials such as slings, shackles etc. will be stored in designated areas.
Escape routes will not be restricted.
Maintain free access to safety equipment.
Waste bins must be used to collect rubbish.
At no time will any flammable material be stored or used in the workshop area or rig floor.
Paints and chemicals should be stored in appropriate containers and never stored to with other flammable liquids or gases.
Repair all faulty tools and put back in the store.

SAFE BEHAVIOUR
You have the obligation to stop an unsafe operation.
Horseplay is not permitted at the restricted areas such as workshop, stacked tool areas etc.
The use of Personal Protective Equipment (PPE) is mandatory for all restricted areas, all manual jobs and when lifting is taking place.
Loitering is prohibited for all employees, contractors, vendors/suppliers and visitors during mobilization and demobilization exercises except for those actively involved in these activities.

HAND TOOLS
Inspect your tools before use.
Secure your tools when working at heights.
Clean and store tools on completion of task.
Use only knives with blade locking mechanism and cut away from the body.
Disconnect and shut off any energy supplies when tools are not being used.
Use only air driven portable tools in hazardous areas.
Always choose the right tools for specific job.

EXTRA EYE PROTECTION IS REQUIRED WHEN USING THESE TOOLS
Use goggles or face shield when changing tong dies.
Using a hammer and chisel.
Using a high-pressure wash-down gun.
Mixing chemicals.
Using grinders.
Using scraping brush.
Wear safety glasses under face shield for added protection.

HOW TO AVOID STRUCK BY HAZARDS
Do not stand or walk below hoisted loads.
Prior to lifting, ensure the load is clear of all obstructions and any fastenings have been removed.
Respect HSE signs and barriers.
Avoid climbing on containers and stacked materials and never stand between loads and walls.

GENERAL SAFE WORKING PRACTICES
Immediately report any injuries.
Do not use compressed air or wash down gun to clean your clothes and do not aim it to your body.
Always have at least one hand onto the handrail at all times and do not carry any tools or equipment with both hands when going up/down a ladder.
Loose clothing must not be worn around machinery.
Gas lighters are not allowed.

PERSONAL PROTECTIVE EQUIPMENT (PPE)
Personal Protective Equipment (PPE) is the last line of defense against many occupational hazards as identify in the oil and gas industry today. A reasonable number of work related injuries today would have been prevented, if the right PPE were used. PPE is mandatory and it is there to save life and prevent occupational related injuries. Remember to identify the right PPE to use when planning a given task. It would be a good practice to always maintain your PPE and not abusing it.
Minimum PPE requirements for a given task:
Coveralls.
Non-metallic hard hats.
Steel toe safety boots/shoes.
Safety goggles with side shields.
Hand gloves.
Ear muff/plug when in an area with noise level of 82 db and above.
Consult the material safety data sheets (MSDS) when working with hazardous materials for the appropriate PPE to use.
Nose mask or respiratory protection must be worn to protect one from airborne contaminants.
Use fall protection such as safety harness when working at height above 2 meters or 6 ft 7 inches.
Note: The HSE Officer or your Supervisors will provide Training in the correct use of PPE.

FIRST AID
First Aid is the immediate and urgent care given by a person to another who has been injured or has been suddenly taken ill.

URGENT CARE
In case of serious injury or sudden illness, while waiting for help, give immediate attention to the following first aid priorities:
Effect a prompt rescue like remove an accident victim from water or from fire.
Ensure that the victim has an open airway and give mouth-to-mouth or mouth-to-nose artificial respiration, if necessary.
Control severe bleeding.
Give first aid for poisoning, or ingestion of harmful chemicals.
Once emergency measures have been taken to ensure the victim’s safety, the following procedures should be carried out:
Do not move a victim unless it is necessary for safety reasons. Keep the victim in the position best suited to his/her condition or injuries; do not let him/her get up or walk about.
Protect the victim from unnecessary manipulation and disturbance.
Avoid or overcome chilling by using blankets or covers, if available. If the victim is exposed to cold or dampness, place blankets or additional clothing over and under him/her.
Determine the injuries or cause for sudden illness. After immediate problems are under control:
Find out exactly what happened. Information may be obtained from the victim or from persons who were present and saw the accident, or saw the individual collapse in the case of sudden illness.
If the victim is unconscious and has no sign of external injury, try to obtain proper identification either from papers carried in billfold or purse, or from bystanders, so that relatives may be notified.
Examine the victim methodically but guided by the kind of accident or sudden illness and, needs of the situation.
Loosen constricting clothing but do not pull on the victim’s belt in case spinal injuries are present.
Open or remove clothing if necessary to expose a body part in order to make a more accurate check for injuries.
Note the victim’s general appearance, including skin discoloration and check all symptoms that may give a clue to the injury or sudden illness.
Check the victim’s pulse. If you cannot feel it at the wrist, check for a pulse f the carotid artery at the side of his neck.
Check if the victim is awake, in stupor or unconscious.
If the victim is unconscious, look for evidence of head injury. In a conscious person, look for paralysis of one side of the face or body. See if the victim shows evidence of a recent convulsion.
Check the expression of the victim’s eyes and the size of his pupils.
Examine the victim’s trunk and limbs for open and closed wounds or for signs of fractures.
Check the front of the victim’s neck to determine whether he/she is a laryngectomee.
If poisoning is suspected, check for stains or burns about the victim’s mouth and source of poisoning nearby, such as pills, medicine bottles, household chemicals or pesticides.
Apply emergency dressings, bandages, and splints.
Do not move the victim unless absolutely necessary.
Plan action according to the nature of the injury or sudden illness, the needs of the situation, and the availability of human and material resources.
Utilize proper first aid measures and specific techniques that, under the circumstances appear to be reasonably necessary.
Remain in charge until the victim can be turned over to qualified persons such as a physician, an ambulance crew, a rescue squad or a police officer or until the victim can take care of himself or can be placed in the care of the relatives.
Do not attempt to make a diagnosis of any sort or to discuss a victim’s condition with bystanders or reporters



BASIC FIRE FIGHTING AND PREVENTION:
Fire is a product of a chain chemical reaction between three elements namely oxygen, heat and fuel when combined in their proper range of concentration. Fire is the most devastating hazard of the workshops and the rig platform. Poor housekeeping most often causes fire and explosion could result from fire out break.



THE FIRE TRIANGLE



FIRE AND EXPLOSION PREVENTION
Poor housekeeping and wrong/bad equipment handling cause most fire incidents. The first step in preventing disastrous fire incidents includes:
Maintain a good housekeeping practice.
Eliminate the cause(s) of the fire.
Control and extinguish the fire when it occurs.

FIRE AND EXPLOSION IN THE WORK AREAS

THE WORKSHOP:
Always keep the workshop environment tidy.
Floors should be swept and oil deposits cleaned where it exists.
Combustible materials should be kept away from wielding areas.
Avoid operating on combustible floors and walls.
Fire extinguishers should be stationed at strategic points in the workshop, must be on a hook at least 1.5 meters from the ground level, be accessible and visible.
Fire extinguishers should be refilled or replaced once discharged.
Fuel or flammable liquids should be stored in specified fire free areas.
Maintain good ventilation in the workshop; always keep doors and windows open and exits clear of obstacles.
Fire fighting drills have to be carried out monthly or at least once every quarter according to location requirement. Staff must be trained on the use of any new fire fighting equipment installed at any time.
Emergency procedures in the case of outbreak of fire must be displayed in the base and at locations along with a map indicating the location of fire extinguishers and muster points.
Qualified personnel must do electrical installations. Make sure equipment ratings are properly checked before connecting them to power supply.

THE RIG:
Smoking is only allowed in designated areas.
Don’t tamper with the rig electrical power supply without permission from the rig electrician. Always crosscheck the supply with our own meter before connecting your equipment. Note: Improper connection causes sparks.
If you notice fire, call the rig Safety Officer immediately to switch on fire alarm and attack the fire with correct extinguisher if safe to do so.



THE FIRE ALARM AND EVACUATION PROCEDURE ON NOTICING FIRE

ACTIONS INSTRUCTIONS

Raise alarm: Shout fire! Fire!! Fire!!! Also, sound the fire
Alarm and use public address system if available to tell people the area on fire.
Call: Radio or telephone personnel to call the fire
Service stations using the fire emergency numbers stating clearly location of fire.
Extinguish Fire: If only safe to do so. Use nearest available
equipment e.g. fire extinguisher or reel hose.
Evacuate building: Leave the building if unsafe to fight fire.
Shut the door after you (do not lock).
Go to the nearest assembly or muster point.
ON HEARING THE ALARM
Evacuate building: Switch off electrical appliances e.g. A/C, PC
and lights.
Close door after you and if possible do not lock.
Leave building through nearest exit.
Mustering: Go to the nearest assembly/mustering point.
Take along your visitors/client.
Do not re-enter the building under any
Circumstance until the emergency is declared over.

HEALTH OF PERSONNEL:
All personnel must undergo a fully pre-employment medical check up by the company recommended Clinic. Field Personnel must have health certificate of fitness for offshore work.
Employees should maintain high hygienic standard to safeguard their good health and those of others.
At no time should an employee on duty:
Work under the influence of alcohol or un-prescribed drugs.
Suffer from communicable diseases.
Have any condition, which will impair their judgment or ability to carry out their duties efficiently and in safe manner.
Should any employee feel unwell at any time of operation, he/she should go and receive medical attention. If it is at locations, report to MEDIC in charge of the location immediately.

EMERGENCY PROCEDURES:
An emergency drill on fire is carried out regularly at least once every quarter to test employees’ preparedness, alertness and prompt response in emergency situations.
In an emergency situation, alarm is used to inform workers of impending danger. Alarms are responded to with strict attention because it is the only informant of impending dangerous situation.

















CHAPTER TWO

LOGGING WHILE DRILLING (LWD)

The logging while drilling operations includes the recording of data from the respective formation being encountered while drilling operation is going on. These data collected provides the LWD Engineer information on the Drilling Efficiency, directional Surveying, formation evaluation and Geo steering. The LWD operation also helps the Engineer identify the Formation encountered (whether Sand, Shale, Liquid, Gas region) during the drilling operation. Equipment used in carrying out the LWD operation includes:
Telemetry Systems
High speed central interface module (HCIM)
Directional Sensors
Dual gamma ray (DGR)
Electromagnetic wave resistivity (EWR)
Stabilized litho density (SLD)
Compensated thermal density (CTN)
Drill string Dynamic sensor (DDS)
Pressure while Drilling (PWD)

The Telemetry Systems
This is an equipment which serves as a media through which data could be transmitted from the down-hole sensors to the surface in real time. There are three types of Telemetry system
1. Negative mud pulse
2. Positive mud pulse
3. Electromagnetic

Negative mud pulser: This telemetry system is usually run at the top of the LWD tool string to achieve minimum bit-to-sensor spacing. The negative pulser is powered by a lithium battery.
Positive mud pulser: There are two types of positive mud pulsers:
1. Standard positive mud pulsers (DWD)
2. High-temperature positive mud pulsers (SOLAR).
The positive mud pulsers are usually Turbine powered.



The HCIM (High Speed Central Interface Module)
This HCIM is the Main controller of the FEWD (Formation Evaluation While Drilling) system. As the main controller, or bus master, the HCIM is responsible for polling the sensors for their data, storing data from the non-smart sensors, and formatting the data for real-time data transmission. Both negative pulse and positive pulse telemetry is available for real time transmission with the HCIM. Negative pulse telemetry utilizes the Smart driver Controller (SDC), while positive pulse telemetry utilizes the PCD-K and TM. The HCIM is also responsible for the supply of battery power to some of the sensors like the DGR, EWR and PWD. It serves as an intermediary between the sensors and the LWD engineer i.e. the LWD is able to communicate with the other LWD equipment (Sensors) down-hole through the HCIM.
Directional Sensors
The Directional Sensors measures the orientation of the LWD tools with respect to the earth’s magnetic and gravitational fields in order to compute the azimuth and inclination of the well-bore and indicate the gravity (high-side) and magnetic tool-face orientation of steerable drilling tools. There are three types of directional sensors:
1. PM (Position Monitor): This sensor is used in conjunction with the negative pulse telemetry systems.
2. PCD (Pressure Case Directional): This is a sensor used with the DWD positive pulse.
3. DM (Directional Module): This is a high temperature sensor and it is used with the SOLAR 175 standard positive telemetry system.

The DGR (Dual Gamma Ray)
The DGR sensor is made up of two opposed banks of Geiger-Muller tubes with two independent detector circuits. This redundant configuration provides two independent natural gamma ray logs. The count rates from the two detector banks are typically combined in order to optimize statistical precision. However, in the unusual event of failure of one detector bank, a corrected gamma ray log can be produced from the second bank. The Applications of the DGR include:
1. In well correlation
2. In Logging of record
3. In Directional Control
4. Helps in enhancing interpretation of wire-line logs








The EWR (Electromagnetic Wave Resistivity


The EWR is a state-of-the-art, high frequency induction resistivity sensor. This tool comprises four radio-frequency transmitters and a pair of receiver antennas. By measuring both the phase shift and attenuation from each of the four transmitter-receiver spacings, eight different resistivity curves with differing depths of investigation can be provided. The Applications of the EWR includes:
1. Resolving of thin sand beds surrounded by shale.
2. Making of deep measurements before invasion.
3. Improving identification of hydrocarbon/water contacts.
4. Detecting of movable hydrocarbons.

SLD (Stabilized Litho Density)




The SLD sensor comprises two gained-stabilized, 254-channel spectral scintillation detectors and a Cs 137 gamma ray source housed in a steel drill collar. Overlying the source and detectors is a special stabilizer blade containing three low-density windows. The stabilizer blade emulates the detector pad windows collimate the gamma rays and focus the measurement. The Operating Applications of the SLD include:
1. Rapid sampling for density-derived caliper
2. Bulk density
3. Photoelectric effect
4. Borehole standoff
5. Wire line-quality density measurements.
Note: In Drillog Petro-Dynamics, the modified form of the SLD is the ALD (Azimuthal Litho density).


CTN (Compensated Thermal Density)



The CTN sensor is a new slim hole neutron porosity tool designed for logging boreholes ranging from 5.875” to 6.5” in diameter. The CTN sensor can be combined with the slim hole EWR, DGR, SLD, and PWD sensors to provide “triple-combo” logging services slim holes. The CTN employs redundant banks of He3 neutron detector at both the near and far spacing added reliability.
The Operating Applications include
1. Porosity measurements
2. Hydrocarbon typing
3. Cased-hole logging

DDS (Drill string Dynamic Sensor):
The DDS sensor is a three-axis shock and vibration sensor whose electronics and accelerometers are mounted on the insert of the DGR sensor. Tri-axial accelerometers measure lateral, tensional, and longitudinal vibration. Average, peak, and instantaneous
acceleration data are recorded. Real time analysis of the data can be used to detect and identify common causes of damaging down-hole vibration, such as bit bounce, lateral shock, stick/slip and PCD bit whirl. The DDS sensor is run as an additional sensor on the negative pulser inside the gamma insert. It provides down-hole vibration information from three orthogonal accelerometers that can be used to prevent tool failures. High vibrations have been correlated to drill string failures and to the failure of the down-hole tools, such
as MWD tools. When high vibration loads are detected, drilling parameters (e.g. rpm, WOB) can be modified to reduce these vibrations and reduce the risk of tool failures.

PWD (Pressure While Drilling):
The PWD provides annular pressure, and temperature measurements. Annular pressure is transmitted in real time every 6 to 30 seconds and displayed as an equivalent mud weight. Pressure and temperature data are also at a more frequent sampling rate (as fast as every 2 seconds) and recovered at the end of each bit run. The data can be displayed as both depths based and time based logs to facilitate interpretation of drilling and non-drilling events.
PWD tools are compatible with both negative and positive pulser and electromagnetic telemetry systems.
Operational Applications include:
1. LOT, lost circulation
2. Flow/Kick detection
3. Hole cleaning and collapse
4. Monitor mud properties
5. Optimize drilling practices
6. Under balanced drilling

LITHIUM BATTERY:
The LWD tools are being powered by the lithium battery; this battery is uniquely made for this purpose and should be handled with care. The Lithium battery is made with Lithium Thionyl; Chloride as the Electrolyte and Carbon as the Anode.


Components of the Lithium Battery:
Can: This houses the cell.
Electrolyte: Either Thionyl chloride or Sulfuryl Chloride. It is needed to conduct electricity.
Separator: It is needed to separate the Cathode from the Anode. It also allows ions pass freely while keeping cathode and anode apart.
Collector: Serve as a conduit, for collecting electrons from the positive terminal and sending electrons to the carbon cathode.
Cathode: Receive the by products of the reaction. It is made up of Carbon.
Anode: To oxidize (donate electrons), there by making electron flow possible. It is made up of Lithium.
































CHAPTER THREE

MEASUREMENT WHILE DRILLING (MWD)
The Measurement While Drilling department (MWD) is a recent introduction to all drilling companies so far. The function of the department as the name implies, is to take data (readings) in the drilling well while the actual drilling is being carried out. Before the birth of this department, drilling work had to be halted or delayed at different stages in order to take the readings in the well. The new technologies used by the MWD department makes it very useful in terms of accuracy of readings and more importantly time conservation, which is a very important economical consideration in drilling of an oil well.
The chief components mainly required for evaluation in the MWD department are the Sand and Shale contents of the soil. Soil samples usually give readings of a sample having both sand and shale combinations in different proportions. This information enables the driller to know when he is approaching an oil reservoir or when he has deviated. Other readings taken include Magnetic Field Strength, Dip Angle and Azimuth.


THE MWD MODULES
The MWD makes use of special cylindrical tools referred to as the MWD modules. There are basically four types of MWD modules, they are:
The battery.
The electronics.
The pulser.
The gamma ray tube.
Mule shoe.


The MWD modules are usually assembled together in different combination referred to as configuration. This assembly of MWD modules is referred to as the MWD Monel. The MWD Monel is introduced into the drill well through along with the mud motor on which it seats.

THE BATTERY



As it is not convenient to run a wire into the drill hole to supply electricity to the MWD Monel, the battery is used to supply the needed power to the system. The battery has a voltage of 28 - 29 volts. It is usually enclosed in a tube called the "bent Hosing".
The battery possesses a 6-pin 4-plug configuration at one end and a 4-pin 6-plug configuration at the other end. These two ends are referred to as the up hole and down hole ends respectively. There are two types of battery commonly in use they are the lithium battery and the alkaline battery. The lithium battery is generally preferred because of its durability (up to 200 hours).
The battery must be connected below the electronics, and up to two may be used at one for prolonged period of time if necessary.


THE ELECTRONICS
The electronics is the control unit of the MWD tool. It is made up of three parts.
The thermometer
The accelerometer
The magnetometer



The thermometer is used to measure the variation of the temperature while drilling. They can withstand temperatures less than or equal to 150 degrees centigrade.
The accelerometer is used to measure the inclination while drilling. Where, inclination is defined as the angle of the tool with the vertical (or true north). The inclination is not constant.
The magnetometer is used to measure the dip angle, Magnetic field strength, magnetic tool face and gravity.
NOTE: The electronics contains 3 accelerometers and 3 magnetometers, which are placed in the x, y, and z-axes.

THE PULSER



The Pulser sends information (data) up hole in the form of signals through pulses sent through the mud as a result of change in pressure. The MWD DRT decodes the pulses, which travel to the surface. They tell the conditions existing in the MWD at any point in time. The pulser consists of two parts; Pulser driver and Oil pulser

Pulser driver - This has two solenoids in it. When current passes through them it causes the solenoids to move apart and this motion pushes the puppet, which is in the oil pulser. When these solenoids move a certain distance apart, a force of attraction draws them back together again and this pulls the puppet. The pulling and holding interval of the solenoid is a function of the pulse width (usually preset). Puppet pulses should range from 0.98 to 1.5 on a dial.
Oil poppet - This is filled with incompressible oil that can withstand high pressures. The pressure has an electronic switch, which is sensitive to flow in the mud. Once there is a mudflow the electronics switch is activated and sends signals to the microprocessor in the electronics, which in turn sends current to the pulser driver.

THE GAMMA RAY TUBE

The gamma ray tube has a scintillating detector (it detects radioactivity in the formation) that is used to measure the "counts of radioactive substances" in the hole. Maximum gamma count is 150. The reading from the gamma is sent upwards to the depth encoder

The Interconnect Module
A device known as the interconnect module is used in the MWD department to join two modules together. It is usually placed in between two of any of the MWD modules (Pulser, Gamma, Battery or Electronics) in any configuration required to take reading from the drill hole. The interconnect passes signals by means of pulses through probes at the core of its shaft.
Other functions of the inter connect module include: Flexibility, centralization and shock absorption of the MWD monel.




INTERCONNECT MAKE – UP PARTS.
1. The interconnect shaft: This is the most vital part of the inter -connect. It is a cylindrical - like tube with pins and holes (plugs) on each end. The two ends of the interconnect are referred to as the up hole and down hole ends. The up hole end consist of 6 pins and 4 plugs, whereas the down hole end consists of 4 pins and 6 plugs. The alternate pins and plugs on both ends of the inter connect are linked together by probes running through the inter connect shaft.
2. The bomber: This is a padded shock resistant hollow casing used to house the inter connect shaft
3. The bow springs: The bow springs are usually four in number for every one interconnect module.
They are attached at equal distances apart around the interconnect bomber with pins.
4. Bow spring retainers: The bow spring retainers used to connect the bow springs firmly around the bomber.
5. Spacers: These are flat, circular components similar to the washer used with bolts and nuts except they are much larger. They are used to reduce the gap between the bow spring retainers and the compression springs, and hence making the interconnect set up more intact.
6. Compression springs: These are hard refractory steel springs mainly responsible for withstanding heavy shock.
7. Threaded rings: These are hollow cylindrical components made from copper, which have external threading. They enable the protectors to be screwed on.
8. O-rings: These are round rubber accessories which are placed on special grooves in the interconnect shaft. They ensure easy slipping on and off of other components along the interconnect shaft during assembly and dismantling. The O-rings are also used to fasten split rings to the interconnect shaft.
9. Split rings: These are semi-circular in nature. They are of different sizes and have external grooves. Two split rings each are connected on each side of the interconnect shaft in special slots and are held together by O-rings.
10. The protector: This is a round, copper cup-like housing used to protect the probes in the interconnect shaft during handling and transportation and also against foreign bodies such as water and mud. They have an internal threading which enables it to be screwed unto the inter connect via the threaded rings.

TROUBLE SHOOTING THE INTERCONNECT SHAFT.
It is important to the MWD technician that the inter connect is confirmed to be in a perfect working condition before it is carried out to the rig site. Tests are carried out on the interconnect shaft and these operations are referred to as troubleshooting. Two tests are usually carried out to test the interconnect shaft. They are: The Continuity Test and The Insulation Test



The Continuity Test
This test is usually carried out after the interconnect module has been dissembled and cleaned. Before reassembling, the inter connect is tested for a break between the down hole and up hole ends. The test carried out for this purpose is referred to as the continuity test.
Procedure:
1. The interconnect shaft is placed on two wooden (insulated) stands.
2. A module break out unit (MBU) is connected leading to the up- hole end of the inter connect. The lead cable has an alternate 4 pins, 6 plugs configuration to match the 6 pins, 4 hole configuration of the up hole end of the inter connect.
3. The down hole ends of the inter connect are connected to the return cable, leading it back to the MBU. The 6 pins, 4 holes configuration of the return cable matches the 4 pins, 6holes configuration of the down hole end of the inter connect.
4. The switches of the Module Break out Unit are all set to the break position.
5. A multi-meter is used to test for the flow of electrical current by connecting its positive and negative ends to the positive and negative outlets of the MBU. This operation is done ten times serially, for the 10 positive and 10 negative outlet holes of the MBU.

Inference/Observation:
The beeping sound of the multi-meter indicates that there is a flow of current between the up hole and down hole (from +ve to -ve) ends of the inter connect when the circuit is closed. This inter connect shaft is in good working condition.

The Insulation Test:
The insulation test is carried out in order to test whether there is a bridge in the circuit between the probes in the interconnect shaft.
The set up is similar to that of continuity test except that the multi-meter is replaced with a type of resistor referred to as omega. The reading on the omega should read infinity to indicate the insulation between the probes.
Procedure:
1. Same as steps 1-4 above.
2. The omega is used to test each of the probes of the 10 probes of the interconnect shaft for a bridge in current by connection the Omega to the positive and negative ends to the positive and negative outlets of the MBU. This operation is done ten times serially, for the 10 positive and 10 negative outlet holes of the MBU.



MULE SHOE/MULE SHOE SUB:
The Muleshoe functions normally by employing the Helix to offer a guide for seating the MWD tool into a specific orientation to be able to measure the tool face
Orientation referenced to the tool face of the MWD probe. The software is also designed to allow the operator to measure any offset of the Muleshoe to the tool face of the bottom hole assembly.
Secondly, the Muleshoe also contains the main orifice into which the pulser main signal poppet projects into to create the pressure pulse. There are five different orifices sizes: 1.28”, 1.35”, 1.40”, 1.50”, 1.60” OD used in the 6.5” and 4.75” Muleshoe sleeves. The 3.5” Muleshoe sleeve has three options for orifice sizes: 1.21, 1/23” and 1.25” OD. The main orifices are easily changed on the job site to accommodate the various flows that may be encountered through the course of a job.
The Muleshoe subs are subs specially designed and cut to receive and anchor the Muleshoe sleeves. The subs are designed to match the mating threads of the collars being used. It is recommended that the subs be cut from a non-magnetic material to insure spacing from the magnetometers in the MWD tool.





















CHAPTER FOUR

DIRECTIONAL DRILLING (DD)

The Directional Drilling department is directly responsible for the actual drilling of the well. This department receives information from the MWD Department. The data used by this department include:
Azimuth - This is the angular distance of the well from the north.
Magnetic field strength - This is measured in Gauss. The value of the magnetic field strength should not exceed a reading of 32 by more or less than 0.05. That is, from 31.95 to 32.05.
Dip angle - this is the angle made by the magnetic north and the horizontal. It is fairly constant at a particular location.
Light side - this is a face of the mud motor, which is usually scubed along its entire length.
Tool face - This is the horizontal component of direction in which the tool faces (i.e. the direction the bit of the drill tool faces). It is useful in determining the angular position of the mud motor.

THE MUD MOTORS
The motors are the tools used for the drilling operation. It powers the drilling bit which actually bores the hole that would lead to the environment where the crude oil could be drilled. The mud motors used by the company were supplied by Drillex. Drillex positive displacement motors comprise of four major elements, from top to bottom include:
1. The By-pass valve Assembly
2. The Power Section
3. The Transmission Assembly
4. The output shaft/Bearing Assembly

The By-Pass valve:
The By-pass valve is used to fill the string when tripping in hole and to empty the sting when pulling out of the hole, thus avoiding a wet trip.
It is fitted above the power section in its own removable sub. The valve remains open until the pressure of the flowing drilling fluid exceeds the spring stiffness of the valve. The flow rate required to close the valve is below the minimum specified working flow rate of the motor.
The Power Section:
The power section converts the hydraulic fluid energy of the drilling fluid into mechanical horsepower. The mechanical horse power of a multi-lobe rotor/stator power section is the product of high output torque and slow rotational speed. The power section consists of the steel rotor and elastometer stator.
Transmission Assembly:
The transmission assembly as its name suggest, transmits the rotational speed and torque produced by the power section to the output shaft/Bearing assembly. The transmission must be capable of absorbing the downward thrust generated by the power section and allow the rotor to remain in the correct axial relationship with the stator.
Output Shaft/Bearing Assembly:
The output shaft is a rigidly constricted hollow steel component that is supported within motor casing by radial and thrust bearings. The majority of the drilling fluid passes through the center of the output shaft to the drill bit.
The thrust bearing are capable of accepting the downward force from the rotor and reactive force from the weight-on-bit which operates in the upward direction. The rapid support bearing consist of either an elastometer banded to a steel line running on a hard Chrome journal or tungsten carbide lined steel sleeve wear surfaces running against each other





















CHAPTER FIVE

RIG COMPONENTS.



Modern rigs make use of the rotary rigs to drill holes. In order to learn about the components that it takes to make a hole, it is convenient to divide them into four main systems. They are;
POWER SYSYTEM
HOISTING SYSTEM
ROTATING SYSTEM
CIRCULATING SYSTEM


1. POWER SYSTEM.
Every rig makes use of powerful internal combustible engines as its prime power source. Rig engines today do not require gasoline as a fuel, but diesel. Also, rigs require more than one engine to provide the needed power.
Gas engines use spark plugs to ignite the fuel-air mixture in their combustion to produce power. On the other hand, diesel engines do not have spark plugs, instead the fuel-air mixture is ignited by heat that is generated inside the engine. Any time a gas is compressed its temperature rises such that if compressed enough, it gets hot enough to ignite. There fore, diesel engines are sometimes referred to as compression-ignition engines, while gas engines are referred to as spark-ignition engines.
A rig may have two to four engines depending on its size. All engines are used together to generate enough horsepower (up to 3000hp) to be transmitted to various components on the rig. Two common methods used to transfer power on the rig are:
Mechanical power transmission
Electrical power transmission

Mechanical Power Transmission:
In this method, engine power is sent to various parts of the rig by machinery such as belts and pulleys.
The power out put by the engines is compounded i.e. all the engines have to be compound together in order to act as one. To do this, a hydraulic coupling or torque converters are mounted to each engine. A shaft called an out put shaft is comes out of each hydraulic coupling, which turn due to engine power. The shafts are then mechanically linked together with pulleys and chains.


Electric Power Transmission:
The diesel-electric power is the dominant method used to drive most of today's rigs. Diesel engines drive large electric generators, which in turn produce electric power that is sent through cables to electric switch and control gears. From here the electricity goes through additional cables- that are attached directly - to the equipment involved.
The advantages of the electric power transmission over the mechanical power transmission are:
It eliminates the entire heavy, complicated compound and chain drive.
Alignment problems are done away with.
Engine noise for the crew is reduced as the engines can be placed far away from the rig floor.
2. HOISTING SYSTEM.
The hoisting system is made up of:
The draw works (Hoist).
The wire rope.
The crown block.
The traveling block
The mast (derrick).

The draw works: This consists of a revolving drum, around which the wire rope, called the drilling line is wrapped.
It also has a cat shaft on which the catheads are mounted.
It also has other cat shafts, clutches, chain- and -gear drives for speed and also, a main brake, which has the ability to stop the drum. The main brake is assisted by the auxiliary hydraulic brake or electric brake to help absorption caused by the heavy load.
The wire rope: This is common to the ordinary fiber rope except that as the name implies it is made up of steel wires. The sizes range from 1 1/8 to 1 1/2 inches in diameter. The wire rope is designed mainly to withstand heavy load encountered on the rig.
The crown lock and the traveling block: are sets of pulleys which work together to suspend the drilling string. The crown block is the larger of the two. The wire rope or drill line is reeled over each of them in turns several times over, this acts has the same effect several lines. The number of turns depends on the amount of weight that needs to be supported. A large hook, attached to the traveling block is also attached to the equipment for suspending the drill string.
Masts: These are long, elevated metal structures on which the weight of the mud pump, drill, workers etc. They are designed to withstand loads of 0.25 million to 1.5 million pounds and a wind load of 100 to 130 miles per hour.


3. ROTATING EQUIPMENT.
Rotating equipment from top to bottom consists of:
The Swivel.
The Kelly.
The Rotary table.
The Drill string and,
The Bits.

The Swivel:
The swivel has a handle similar to the handle of a bucket, except it is much larger, which fits inside the hook at the bottom of the traveling block.
The swivel is remarkable because it:
Sustain the weight of the drill string.
Permit the string to rotate.
Affords a rotating pressure tight seal and passageway for the drill mud to be pumped down the inside of the drill string.

The Kelly:
The Kelly is a square or hexagonal short piece of pipe attached immediately below the swivel. Like the swivel it is a unit through which drilling mud is pumped on its way to the bottom.
The reason the Kelly is four or six sided is that it serves as a way of transferring rotating motion to the rotary table. The Kelly sits inside a part of the rotary table called the Kelly bushing, which in turn sits inside another part of the rotary table called the master bushing. As the master bushing rotates, the Kelly bushing also rotates and since the Kelly mates with the Kelly bushing the Kelly rotates. And since the drill pipe is connected to the bottom of the Kelly, the pipe rotates as the Kelly rotates. The bit also rotates because it is attached to the drill string.

The Rotary table:
This is the rig floor either powered of the rig power system or its own electric motor. It comprises of several parts, which include the master bushing and he Kelly bushing. It also has a pair of slips accommodated in the master bushing.
A set of slips is a tapered device with strong teeth- like gripping element which, when placed around a drill pipe help to keep the pipe suspended in the hole when the Kelly is being disconnected.




The Drill string:
The drill string consists of the drill pipe and a special heavy walled pipe called the drill collars. Drill collars like drill pipes are tubes through which mud can be pumped.
Drill collars are heavier than the drill pipes and are put on the bottom part of the string to put weight on the bit. This weight presses down on the bit and supports its drilling.
A length of drill pipe is about 30 feet long. Each length of a drill pipe (joint) is threaded at both ends. One end is threaded internally and the other externally. The inside threaded end (the female end) is called the box and the outside threaded end (the male end) is called the pin. When pipe is made up the pin is stabbed into the box. The threaded ends are also referred to as the tool joints.

Bits:
These are devices, which are actually responsible for the creation of the drill hole. The Bits possess teeth, which are responsible for the actual cutting or gourging out the soil formation. They also have passages drilled through them to allow the drilling fluids to exit.


4. CIRCULATION SYSTEM.

Drilling Fluid:
Drilling fluid -also called mud - is usually a mixture of water, clay, weighting material and a few chemicals. Sometimes oil is may be used instead of water, or a little oil is added to the water to give the mud certain desirable properties. Mud is important in that it is used to raise cuttings made by the drill bits to the surface for disposal and also for keeping underground pressures in check while drilling.

Circulation:
The mud pump takes in mud from the mud pit and sends it out a discharge line to a standpipe. The standpipe is a steel pipe mounted vertically on the leg of the mast or derrick. The mud is pumped up the standpipe and into a flexible, very strong reinforced rubber hose called the rotary hose or Kelly hose. The Kelly hose is connected to the swivel. The mud enters the swivel and goes down the Kelly, drill pipe and drill collars and exits at the bit. It then does a sharp u - turn and heads up the hole in the annulus. The annulus is the space between the outside of the drill pipe and the wall of the hole. Finally the mud leaves the hole through a steel pipe called the mud return line and falls over a vibrating screen like device called a shale shaker. The shale shaker screens out the cuttings and dumps them inside one of the reserve pits. On off -shore drill sites, the cuttings are put into a barge, to be transported for disposal at a land site.
The mud drains back into the mud pits and is recycled back down the hole by the mud pumps.
The circulation system is generally a closed one.

Auxiliary Equipment:
Auxiliary equipments are equipment used to ensure maintenance of the drilling mud. They are:
Agitators - These are installed on the mud pits and help to maintain a uniform mixture of liquids and solids in the mud.
Desilters and Desanders - These are used if any silt or sand formation is being drilled. This is because the shale shaker screen is not fine enough to very small particles.
Degasser - As the name implies, this is used to remove gases from the mud, thereby assuring desirable density - Gasses make the mud to be less dense.
Hopper - This is a large funnel - shaped piece of equipment used when adding solid materials like clay and barite to the pit.
Mud house - This is used for storage of sacks and mud materials, to keep the safe and dry until needed.


















CONCLUSION

The students industrial work experience scheme (SIWES) should be recommended for all science and engineering students, since the theoretical knowledge of their course of study is not enough to help them in the demands of the dynamic technological industry, hence, they need exposure to be abreast with the latest technological innovations in the industry.























REFERENCE


DRILLOG PETRO-DYNAMICS SAFETY MANUAL

DRILLOG PETRO-DYNAMICS LABULATORY MANUAL

CDMA TECHNOLOGY

TABLE OF CONTENTS
PAGE
Dedication i
Table of Contents ii
Acknowledgement iv
Introduction v

1. BRIEF HISTORY OF STARCOMMS PLC 1
2. INTRODUCTION TO TELECOMMUNICATIONS
2.1 What is telecommunication? 5
2.2 How telecommunication works 5
2.3 Wireless communication 6
2.3.1 Cellular telephony 7
3. CDMA NETWORK TOPOLOGY
3.1 Difference between GSM and CDMA 11
3.2 CDMA Architecture 14
3.2.1 CDMA Network Structure 14
3.2.2 CDMA Network Areas 18
3.2.3 Signalling in CDMA 20
3.3 Transmission of digital signal in CDMA 22
3.3.1 Modes of transmitting digital signals 22
3.3.2 Cell Site 24
3.3.3 How the Mobile Station (cell phone) works 27
3.4 CDMA Subscriber Services 31


4. BASE STATION SUBSYSTEM
4.1 Introduction 32
4.2 Base Station Controller (BSC) 33
4.3 Base Transceiver Station (BTS) 34
4.3.1 System Overview 34
4.3.2 System Structure 36
5. RADIO UNIT AND ALARM MANAGEMENT
5.1 Introduction 40
5.2 Features 40
5.3 System Description 40
5.4 Alarm Management 43
5.5 Transmission Problem and Solutions 44
Conclusion 47




























INTRODUCTION
Engineering is a practical course. It requires a good knowledge of, not just the theoretical, but the practical aspect of the course. Most Nigerian Universities unfortunately are under-equipped and therefore cannot provide adequate practical knowledge needed in Engineering.
The Students Industrial Work Experience Scheme(SIWES) was set up to enhance the knowledge of Engineering in the sense that while the Universities(lectures) cater for the theoretical aspect of the course, SIWES provides students with the opportunity to work in industries and firms and acquire skills & knowledge in Engineering.
Telecommunications is a very vital tool in our world today. It is practically inevitable in every aspect of life including: businesses, companies, schools, religious gatherings, e.t.c.
In the age of information technology in which EEE is a major stakeholder, telecommunications is a major area of interest which is hardly addressed by the course curriculum. It was in order to redress this imbalance that I decided to use this IT opportunity to acquaint myself of the knowledge of telecommunications with Starcomms Plc.





CHAPTER ONE
BRIEF HISTORY OF STARCOMMS PLC
Starcomms, Nigeria’s leading telecommunications operator and leading "triple-play" (mobile, fixed wireless voice, wireless broadband) provider, is quoted on the Nigerian Stock Exchange having being listed on July 14, 2008. It is the first telecommunications operator in Nigeria to be listed on the domestic Exchange. Starcomms commenced operations in 1989 with a customer base of less than 2,000, at the end of June 2008, the network had crossed over 2.9 million subscribers; making it the 4th largest telecommunications operator and largest CDMA 3G Mobile network in the country. It is also the first CDMA 3G network to cross the one million subscriber base in Nigeria.
Between 2002 and 2005, Starcomms focused on providing fixed wireless services (due to PTO license restrictions), becoming the leading fixed line provider in the country. Starcomms is the leading provider of 3G services in Nigeria using CDMA 2000 EV-DO and was the first company in Africa to launch EV-DO high-speed broadband services in June 2006. In February last year, the network launched its nationwide mobile services after being awarded a 10-year (renewable) technology-neutral national unified license in May 2006, which allows it to offer the full range of telecommunication services on a national basis, as well as international gateway services.
Starcomms is currently present in 28 major cities covering over 100 towns while work is in progress to provide coverage in 31 major cities, 140 towns and 20 States. Major cities such as Lagos, Abuja, Port Harcourt, Kaduna, Kano, Zaria, Ibadan, Benin, Ijebu Ode, Shagamu, Calabar, Warri, Owerri, Oyo, Uyo, Ogbomosho, Abeokuta, Aba, Onitsha, Asaba, Maiduguri, Sapele, Umuahia, Nnewi, Awka, Ilorin and Katsina are on the network. In 2007 Starcomms was named both Nigerian Telecoms Company of the Year (Nigeria Telecoms Awards) and Nigerian Wireless Telecoms Company of the Year (Nigeria Information Technology and Telecoms Awards)
Commercially launched in 1999, Starcomms is today the largest Fixed Wireless Telecommunications provider in West Africa. With our deployment of the world class CDMA technology in 2002, they have exponentially broadened their subscriber base to over 2,900,000 customers all over Lagos, Ibadan, Port-Harcourt, Maiduguri, Kano, Aba, Onitsha, Abuja, Asaba, Zaria, Benin, Kaduna, Abeokuta, Calabar, Warri, Owerri, Uyo, Ilorin, Shagamu, Ijebu Ode, Calabar, Sapele, Umuahia, Awka, Nnewi, Kano, Ogbomosho and Katsina - a subscriber base that continues to grow in leaps.
In 2006, Starcomms launched 3G EVDO mobile broadband Data service that gives customers a smart, fast, convenient and mobile access to the internet (a first in Nigeria, and in West Africa). This followed the launch of the Value added services Fun Box; offering a variety of services that enhance the lifestyle of our users. These services include: 'Dash me credit' (airtime transfer), 'Talk Your Text' (Voice SMS), Voice conferencing involving up to 30 users at a time. Starcomms were the first operator to launch 'Instant messenger' on mobiles in Nigeria.

Still in 2006, Starcomms took yet another giant leap when the Nigerian Communications Commission (NCC) granted it a Unified License. This enabled them to operate as a mobile CDMA network nationwide. Early in 2007, they redefined voice services, in 2 distinct categories; Mobiles and Fixed. Their 0702-8 mobile number series, introduced Freedom Roaming Tariffs for mobiles and the use of RUIM cards - offering subscribers full mobility – subscribers can now roam from one Starcomms coverage city to another on the same number and charging plan.
As the African leader in the commercialization of CDMA, Starcomms continues to demonstrate its expertise in maximizing the performance of new technologies across its infrastructure equipment and subscriber products in order to meet customer expectations.
Today with their 0702-8, 0702-9, 08190, 08191 series, they remain the most poised in providing customers’ great experience of mobile and fixed/wireless with a wide range of flexible and innovative services some; the first of their kind in Nigeria. They have continuously partnered with major telecommunication and service providers around the world. At Starcomms, they believe in deploying the latest telecommunication equipments for future communication needs. With investments in innovative technologies running into billions of Naira, they consistently seek to provide better voice and data services for their consumers.
Also, they seek to encourage local businesses (for instance, all their CDMA base stations were built by local contractors and are maintained by them).
With investments in innovative technologies running into billions of Naira, we consistently seek to provide better voice and data services for our consumers. They are in strategic alliance with other world class telecommunication providers. These include: Qualcomm, CDG, Huawei, Hisense, Harris, Haier, LG, Neratel, CoolPad, Nokia, Motorola, and ZTE.
The world is demanding more from wireless communication technologies than ever before, and CDMA is positioned to respond to those demands. Add in exciting data services and applications such as wireless email, web, digital picture taking/sending and assisted-GPS position location applications, yet tomorrow they will be asked to do even more.
CDMA, incorporating spread-spectrum technology, works by digitizing multiple conversations, attaching a code known only to the sender and receiver, and then dicing the signals into bits and reassembling them. CDMA enables many more people to share the airwaves at the same time than do alternative technologies.
Starcomms has a long standing history with CDMA. They were the first in Africa to implement CDMA ONE using the IS-95A in 1998, and in 2002 Starcomms expanded its platform and network to provide fully functional fax & data at 14.4 kb/s - a first for Nigeria. In line with their pioneering heritage, and to match global standards, Starcomms implemented Africa's premier CDMA 2000 1X system, and was the first West Africa’s Mobile Operator to offer 3G Services based in EVDO Rev. 0, services upgraded in 2007 by introducing super-fast 3G EVDO Rev.A services.
Starcomms became a public limited company in 2008. It has over 2000 staff nationwide. Its national headquarters is located in Victoria Island, Lagos. It has so many departments including: Human Resources, Finance, Customer Care, Engineering/Technology, and Administration. There are eight other sub-departments under Engineering/Technology which include: Field Operations, Information Technology, Power, Transmission, Switch, Radio Frequency, Project, Planning and Implementation. Each of the departments has their own specific functions of which all of them work towards achieving a clear signal in the network. The heart of the Engineering/Technology is Field Operations because they actually do the bulk of the work.
There are about 170 cell sites in Lagos State with four backbones (BSCs) in Victoria Island, Ketu, Apapa, and Mouka (Ikeja). The cell sites are divided into six zones: A-F with two to three field engineers assigned to each zone. I worked with the engineers in zone E. There were 39 sites in zone E in addition to a customer care centre in Ikotun. The location of the cell sites include: Agbara, Alaba, Alaba Market, Aspanda, Okota, Festac town, Ejigbo, Ojo, Satellite town, Badagry, Kweme, e.t.c.





CHAPTER TWO
INTRODUCTION TO TELECOMUNICATIONS
2.1 WHAT IS TELECOMMUNICATION?
As we all know, communication is the process of sharing ideas, information, and messages with others in a particular time and place. Communication includes writing and talking, as well as nonverbal communication (such as facial expressions, body language, or gestures), visual communication (the use of images or pictures, such as painting, photography, video, or film), and electronic communication (telephone calls, electronic mail, cable television, or satellite broadcasts). Communication is a vital part of personal life and is also important in business, education, and any other situation where people encounter each other.
Telecommunications uses devices and systems that transmit electronic or optical signals across long distances. The IEEE Standard Dictionary (Ref. 2) defines telecommunications as the transmission of signals over long distance, such as by telegraph, radio, or television. Telecommunications usually involves a sender of information and one or more recipients linked by a technology, such as a telephone system, that transmits information from one place to another.
2.2 HOW TELECOMMUNICATION WORKS
Telecommunications begin with messages that are converted into electronic or optical signals. Some signals, such as those that carry voice or music, are created in an analogue or wave format, but may be converted into a digital or mathematical format for faster and more efficient transmission. The signals are then sent over a medium to a receiver, where they are decoded back into a form that the person receiving the message can understand. There are a variety of ways to create and decode signals, and many different ways to transmit signals. They include: Wires and cables, Fibre cables, Radio Waves and Communication Satellites. This report which will be dealing on wireless communication will be focused on Radio Waves of which the former is transmitted through. The different telecommunication systems include:
- Telegraph.
- Telephone.
- Teletype, Telex and Facsimile transmission
- Television.
- Radio.
- Global Positioning and navigation systems.
- Personal Computers.
-Voice over Internet Protocol (VOIP).
2.3 Wireless Communication
Wireless telecommunications use radio waves, sent through space from one antenna to another, as the medium for communication. Radio waves are used for receiving AM and FM radio and for receiving television. Cordless telephones and wireless radio telephone services, such as cellular radio telephones and pagers, also use radio waves. Telephone companies use microwaves to send signals over long distances. Microwaves use higher frequencies than the radio waves used for AM, FM, or cellular telephone transmissions and they can transmit larger amounts of data more efficiently. Microwaves have characteristics similar to those of visible light waves and transmit pencil-thin beams that can be received using dish-shaped antennas.
Wireless communications systems include cellular telephones, pagers, radio telegraphs, satellite telephones, laptop computers, personal digital assistants (PDAs), shortwave radios, and two-way radios.
Currently, telecommunications companies throughout the world are activating more wireless service subscriptions than they are conventional wire-based service subscriptions.
Wireless communications systems involve either one-way transmissions, in which a person merely receives notice of a message, or two-way transmissions, such as a telephone conversation between two people. An example of a device that only receives one-way transmission is a pager, which is a high-frequency radio receiver. Two-way transmissions require both a transmitter and a receiver for sending and receiving signals. A device that functions as both a transmitter and a receiver is called a transceiver. Cellular radio telephones and two-way radios use transceivers, so that back-and-forth communication between two people can be maintained.

Fig1. How wireless telecommunication works

2.3.1 Cellular Telephony
This involves the use of cell phones which combine their portable radio capability with the wired, or wire-based, telephone network to provide mobile users with access to the rest of the public telephone system used by non-mobile callers. Modern cellular telephones use a network of several short-range antennas known as towers that connect to the telephone system. Because the towers have a shorter range and cover a smaller area, often as short as 1.5 to 2.4 km (1.0 to 1.5 mi), frequencies can be reused a short distance away without overlapping and causing interference.
Cell phone towers pick up requests from cell phones for a dial tone and also deliver inbound calls to the appropriate cell phone or deliver calls to people using regular telephones on the wire-based system. To do any of these things, the cell phone must have a singular identity that can be recognized by computers housed in a central mobile service switching centre (MSC). When a cell phone is turned on, it connects by radio waves to the nearest cell tower (tower receiving the strongest signal). The cell towers are spaced so their receiving ranges slightly overlap. This continuous contact makes it possible for the MSC to transfer a call from tower to tower as a mobile cell phone user (in a moving vehicle, for instance) moves from one cell area to another.







Fig2. A Cell Phone and its parts


Cellular telephony is of two categories: mobile and fixed of which the rest of this report is going to be based on the later.
-Cellular Access Technologies
There are three common technologies used by cell-phone networks for transmitting information:
• Frequency division multiple access (FDMA)
• Time division multiple access (TDMA)
• Code division multiple access (CDMA)
FDMA puts each call on a separate frequency. TDMA assigns each call a certain portion of time on a designated frequency. CDMA gives a unique code to each call and spreads it over the available frequencies. The last part of each name is multiple access. This simply means that more than one user can utilize each cell. FDMA is not considered to be an efficient method for digital transmission.
Time Division Multiple Access (TDMA)
TDMA is the access method used by the Electronics Industry Alliance and the Telecommunications Industry Association for Interim Standard 54 (IS-54) and Interim Standard 136 (IS-136). Using TDMA, a narrow band that is 30 kHz wide and 6.7 milliseconds long is split time-wise into three time slots. Narrow band means "channels" in the traditional sense. Each conversation gets the radio for one-third of the time. This is possible because voice data that has been converted to digital information is compressed so that it takes up significantly less transmission space. Therefore, TDMA has three times the capacity of an analogue system using the same number of channels. TDMA systems operate in either the 800-MHz (IS-54) or 1900-MHz (IS-136) frequency bands. TDMA is also used as the access technology for Global System for Mobile communications (GSM). However, GSM implements TDMA in a somewhat different and incompatible way from IS-136. Think of GSM and IS-136 as two different operating systems that work on the same processor, like Windows and Linux both working on an Intel Pentium III

Fig3. TDMA splits a frequency into time slots
Code Division Multiple Access
CDMA takes an entirely different approach from TDMA. CDMA, after digitizing data, spreads it out over the entire available bandwidth. Multiple calls are overlaid on each other on the channel, with each assigned a unique sequence code. CDMA is a form of spread spectrum, which simply means that data is sent in small pieces over a number of the discrete frequencies available for use at any time in the specified range.

Fig4. In CDMA, each phone’s data has a unique code
CHAPTER THREE
CDMA NETWORK TOPOLOGY
As have already explained, CDMA (Code division Multiple Access) which is one of the technologies for transmission of cellular phone networks. In CDMA, each phone’s data has a unique code. All of the users transmit in the same wide-band chunk of spectrum. Each user's signal is spread over the entire bandwidth by a unique spreading code. At the receiver, that same unique code is used to recover the signal. Because CDMA systems need to put an accurate time-stamp on each piece of a signal, it references the GPS system for this information. Between eight and 10 separate calls can be carried in the same channel space as one analogue AMPS call. CDMA technology is the basis for Interim Standard 95 (IS-95) and operates in both the 800-MHz and 1900-MHz frequency bands.
CDMA technology has evolved from the IS95A→IS95B→CDMA2000 1X→CDMA 1X EV→CDMA 1X EV-DO→CDMA 1X EV-DV→CDMA MC 3X→WCDMA→TD-SCDMA. Starcomms highest technology is the CDMA 1X EV-DO where EV-DO stands for Evolution Data Optimised.
In cellular service there are two main competing network technologies: Global System for Mobile Communications (GSM) and Code Division Multiple Access (CDMA). Understanding the difference between GSM and CDMA will allow one to choose a carrier that uses the preferable network technology for his needs.
3.1 DIFFERENCE BETWEEN GSM AND CDMA
-Coverage: The most important factor is getting service in the areas you will be using your phone. Upon viewing competitors' coverage maps you may discover that only GSM or CDMA carriers offer cellular service in your area. If so, there is no decision to be made, but most people will find that they do have a choice.
-Data Transfer Speed: With the advent of cellular phones doing double and triple duty as streaming video devices, podcast receivers and email devices, speed is important to those who use the phone for more than making calls. CDMA has been traditionally faster than GSM, though both technologies continue to rapidly leapfrog along this path. Both boast "3G" standards, or 3rd generation technologies.
EVDO, also known as CDMA2000, is CDMA's answer to the need for speed with a downstream rate of about 2 megabits per second, though some reports suggest real world speeds are closer to 300-700 kilobits per second (kbps). This is comparable to basic DSL. As of fall 2005, EVDO is in the process of being deployed. It is not available everywhere and requires a phone that is CDMA2000 ready.
GSM's answer is EDGE (Enhanced Data Rates for GSM Evolution), which boasts data rates of up to 384 kbps with real world speeds reported closer to 70-140 kbps. With added technologies still in the works that include UMTS (Universal Mobile Telephone Standard) and HSDPA (High Speed Downlink Packet Access), speeds reportedly increase to about 275-380 kbps. This technology is also known as W-CDMA, but is incompatible with CDMA networks. An EDGE-ready phone is required.
In the case of EVDO, theoretical high traffic can degrade speed and performance, while the EDGE network is more susceptible to interference. Both require being within close range of a cell to get the best speeds, while performance decreases with distance.
-Subscriber Identity Module (SIM) cards: In the United States only GSM phones use SIM cards. The removable SIM card allows phones to be instantly activated, interchanged, swapped out and upgraded, all without carrier intervention. The SIM itself is tied to the network, rather than the actual phone. Phones that are card-enabled can be used with any GSM carrier. The CDMA equivalent, a R-UIM card, is only available in parts of Asia but remains on the horizon for the U.S. market. CDMA carriers in the U.S. require proprietary handsets that are linked to one carrier only and are not card-enabled. To upgrade a CDMA phone, the carrier must deactivate the old phone then activate the new one. The old phone becomes useless.
-Roaming: For the most part, both networks have fairly concentrated coverage in major cities and along major highways. GSM carriers, however, have roaming contracts with other GSM carriers, allowing wider coverage of more rural areas, generally speaking, often without roaming charges to the customer. CDMA networks may not cover rural areas as well as GSM carriers, and though they may contract with GSM cells for roaming in more rural areas, the charge to the customer will generally be significantly higher.
-International Roaming: If you need to make calls to other countries, a GSM carrier can offer international roaming, as GSM networks dominate the world market. If you travel to other countries you can even use your GSM cell phone abroad, providing it is a quad-band phone (850/900/1800/1900 MHz). By purchasing a SIM card with minutes and a local number in the country you are visiting, you can make calls against the card to save yourself international roaming charges from your carrier back home. CDMA phones that are not card-enabled do not have this capability, however there are several countries that use CDMA networks. Check with your CDMA provider for your specific requirements.
According to CDG.org, CDMA networks support over 270 million subscribers worldwide, while GSM.org tallies up their score at over 1 billion. As CDMA phones become R-UIM enabled and roaming contracts between networks improve, integration of the standards might eventually make differences all but transparent to the consumer.
The chief GSM carriers in the United States are Cingular Wireless, recently merged with AT&T Wireless, and T-Mobile USA. Major CDMA carriers are Sprint PCS, Verizon and Virgin Mobile. There are also several smaller cellular companies on both networks.
3.2 CDMA ARCHITECTURE
A CDMA network is composed of several functional entities, whose functions and interfaces are specified. The figure shows the layout of a generic CDMA network. The CDMA network can be divided into three broad parts.
3.2.1 CDMA Network Structure
-The Mobile Station is carried by the subscriber.
-The Base Station Subsystem controls the radio link with the Mobile Station.
-The Network Subsystem or Switching system, the main part of which is the Mobile services Switching Centre (MSC), performs the switching of calls between the mobile users, and between mobile and fixed network users.

Fig5. CDMA Network Structure

Mobile Station (MS)
The MS, i.e. the GSM handset, is logically built up from the following components:
• Mobile equipment (ME) – this is the CDMA terminal, excluding the SIM card;
• Subscriber identification module (SIM) – this is the chip embedded in the SIM card that identifies a subscriber of a CDMA network; the SIM is embedded in the SIM card. When the SIM card is inserted in the ME, the subscriber may register with a CDMA network. The ME is now effectively personalized for this CDMA subscriber. The SIM card contains information such as IMSI, advice of charge parameters, operator-specific emergency number, etc.

The Base Station System (BSS)
All radio-related functions are performed in the BSS, which consists of base station controllers (BSCs) and the base transceiver stations (BTSs).
• BSC—The BSC provides all the control functions and physical links between the MSC and BTS. It is a high-capacity switch that provides functions such as handover, cell configuration data, and control of radio frequency (RF) power levels in base transceiver stations. A number of BSCs are served by an MSC.
• BTS—The BTS handles the radio interface to the mobile station. The BTS is the radio equipment (transceivers and antennae) needed to service each cell in the network. A group of BTSs are controlled by a BSC.
The Switching System
The switching system (SS) is responsible for performing call processing and subscriber-related functions. The switching system includes the following functional units:
- Home location register (HLR)—The HLR is a database used for storage and management of subscriptions. The HLR is considered the most important database, as it stores permanent data about subscribers, including a subscriber's service profile, location information, and activity status. When an individual buys a subscription from one of the PCS operators, he or she is registered in the HLR of that operator.
• Mobile services switching centre (MSC)—The MSC performs the telephony switching functions of the system. It controls calls to and from other telephone and data systems. It also performs such functions as toll ticketing, network interfacing, common channel signalling, and others.
• Visitor location register (VLR)—The VLR is a database that contains temporary information about subscribers that is needed by the MSC in order to service visiting subscribers. The VLR is always integrated with the MSC. When a mobile station roams into a new MSC area, the VLR connected to that MSC will request data about the mobile station from the HLR. Later, if the mobile station makes a call, the VLR will have the information needed for call setup without having to interrogate the HLR each time.
• Authentication centre (AUC)—A unit called the AUC provides authentication and encryption parameters that verify the user's identity and ensure the confidentiality of each call. The AUC protects network operators from different types of fraud found in today's cellular world.
• Equipment identity register (EIR)—The EIR is a database that contains information about the identity of mobile equipment that prevents calls from stolen, unauthorized, or defective mobile stations. The AUC and EIR are implemented as stand-alone nodes or as a combined AUC/EIR node.
The Operation and Support System
The operations and maintenance centre (OMC) is connected to all equipment in the switching system and to the BSC. The implementation of OMC is called the operation and support system (OSS). The OSS is the functional entity from which the network operator monitors and controls the system. The purpose of OSS is to offer the customer cost-effective support for centralized, regional and local operational and maintenance activities that are required for a GSM network. An important function of OSS is to provide a network overview and support the maintenance activities of different operation and maintenance organizations.
-Note that the MSC contains no information about particular mobile stations --- this information is stored in the location registers.

Fig6. CDMA Network Elements
Additional Functional Elements
Other functional elements are as follows:
• Message centre (MXE)—The MXE is a node that provides integrated voice, fax, and data messaging. Specifically, the MXE handles short message service, cell broadcast, voice mail, fax mail, e-mail, and notification.
• Mobile service node (MSN)—The MSN is the node that handles the mobile intelligent network (IN) services.
• Gateway mobile services switching centre (GMSC)—A gateway is a node used to interconnect two networks. The gateway is often implemented in an MSC. The MSC is then referred to as the GMSC.
• CDMA interworking unit (CIWU)—The CIWU consists of both hardware and software that provides an interface to various networks for data communications. Through the CIWU, users can alternate between speech and data during the same call. The CIWU hardware equipment is physically located at the MSC/VLR.
3.2.2 CDMA Network Areas
The GSM network is made up of geographic areas. As shown in Figure 3, these areas include cells, location areas (LAs), MSC/VLR service areas, and public land mobile network (PLMN) areas.









Fig7. Network Areas
The cell is the area given radio coverage by one base transceiver station. The GSM network identifies each cell via the cell global identity (CGI) number assigned to each cell. The location area is a group of cells. It is the area in which the subscriber is paged. Each LA is served by one or more base station controllers, yet only by a single MSC (see Fig8). Each LA is assigned a location area identity (LAI) number.

Fig8. Location Areas

An MSC/VLR service area represents the part of the GSM network that is covered by one MSC and which is reachable, as it is registered in the VLR of the MSC (see Fig9).
Fig9. MSC/VLR Service Areas
The PLMN service is the area serviced by one network operator. PLMN comes in three categories:
• Home PLMN (HPLMN) – the HPLMN is the CDMA network that a CDMA user is a subscriber of.
That implies that CDMA user’s subscription data resides in the HLR in that PLMN.
• Visited PLMN (VPLMN) – the VPLMN is the CDMA network where a subscriber is currently registered. The subscriber may be registered in her HPLMN or in another PLMN.
• Interrogating PLMN (IPLMN) – the IPLMN is the PLMN containing the GMSC that handles mobile terminating (MT) calls. MT calls are always handled by a GMSC in the PLMN, regardless of the origin of the call.

3.2.3 Signalling in CDMA
The various entities in the GSM network are connected to one another through signalling networks. Signalling is used for example, for subscriber mobility, subscriber registration, call establishment, etc. The connections to the various entities are known as ‘reference points’. Examples include:
• A interface – the connection between MSC and BSC.
• Abis interface – the connection between BSC and BTS.
• D interface – the connection between MSC and HLR.
• Um interface – the radio connection between MS and BTS.
When it comes to call establishment, CDMA makes a distinction between signalling and payload. Signalling refers to the exchange of information for call set up while payload refers to the data that is transferred within a call, i.e. voice, video, fax etc.
In PSTN, signalling is a means for transferring network-related information between switching nodes, and also between the end office switches and their subscribers. Signalling is used to do the following:
• Request service from the central office switch (via going off-hook).
• Provide central office switch with the information necessary to route a telephone call (via DTMF addressing digits in a specific format).
• Alert destination address of incoming call (ringing).
• Provide status information and call supervision for billing.
• Manage network lines/trunks (set up and teardown calls).
The two forms of signalling used by the network are:
• Channel Associated Signalling (CAS)
• Common Channel Signalling (CCS)
The principal advantage of CAS is that it is inexpensive to implement and can be used on any transmission medium.
However, CAS has the following disadvantages:
• Fraud— “phone freaks” can build boxes to play call setup and teardown tones.
• Interference is possible between signalling tones used by the network and frequencies of human speech patterns.
• Speed—call setup and teardown is slower, less efficient use of resources.
CCS employs a separate, dedicated path for signalling. Voice trunks are used only when a connection is established, not before. Call setup time is quicker because resources are more efficiently used. CCS is the technology that makes ISDN and SS7 possible.
ISDN and SS7 are similar in the sense that they make use of the Primary Rate Interface (PRI) which is divided into E1-PRI and T1-PRI. E1 is two (2) way transmission of digital signal operating at 2.048Mbps and has 32 timeslot/channels (30B+2D at 64 Kbps per PCM channel). T1 is two (2) way transmission of digital signal operating at 1.54Mbps and has 24timeslots/channels (23B+1D at 64 Kbps per PCM channel).
However the standard signalling system for transmitting digital data approved by ITU-T is SS7 because it uses different messaging for call setup and teardown. SS7 lets any SS7-enabled node to talk to any other, regardless of whether they have direct trunk connections between them.
Signalling is of three modes namely:
• Associated Signalling—uses one dedicated path between switches as the signalling link. Examples: ISDN-PRI and E1-CAS.
• Non-Associated Signalling—uses separate logical paths and multiple nodes.
• Quasi-Associated Signalling—uses a minimal number of nodes (preferred for SS7, causes less delay).


3.3 TRANSMISSION OF DIGITAL SIGNALS IN CDMA
3.3.1 Modes of transmitting digital signals
They include:
-By Coaxial cables (E1 cables).
-By Optic Fibre.
-By Microwave (Radio).
-By Satellite (VOIP).
Before transmission can go on, the network specifications/characteristics as well as the availability of the cell-sites should be considered.
3.3.2 Network Specifications/Characteristics:
• Frequency band—Frequency is the number of complete oscillations in a second. The frequency range specified for CDMA is 800 and 1,900 MHz (mobile station to base station).
• Wavelength—This is the length of one complete oscillation and is measured in metres. Frequency and wavelength are related via the speed of propagation. Lower frequencies with longer wavelengths are better suited to transmission over large distances, because they bounce on the surface of the earth and in the atmosphere e.g. television and FM radio transmission. Higher frequencies with shorter wavelengths are better suited to transmission over large distances, because they are sensitive to such problems as obstacles in the line of the transmission path. The frequencies used by mobile systems comprise between the large coverage advantages offered by lower frequencies and the closeness to the receiver advantages offered by use of higher frequencies.
• Bandwidth—This is the amount of frequency range allocation to one application. The bandwidth given to an application depends on the amount of available frequency spectrum. The amount of bandwidth is an important factor in determining the capacity of the mobile system i.e. the number of calls, which can be handled. The bandwidth size for all CDMA modes is 1.25MHz.

• Channels—This is a frequency which can be allocated for the transmission and possibly the receipt of information. Communication channels can be of three forms: simplex, half duplex and full duplex. A simplex channel such as FM radio station uses a single frequency in a single direction only. A duplex channel, such as used during a mobile call, uses two frequencies: one to the MS and one from the MS. The direction from the MS to the network is called uplink. The direction from the network to the MS is called downlink. In CDMA the number of channels is 20 (798 users per channel).
• Duplex distance—The duplex distance is 80 MHz. Duplex distance is the distance between the uplink and downlink frequencies. A channel has two frequencies, 80 MHz apart.
• Channel separation—This is the separation between adjacent carrier frequencies. It is required in order to avoid the overlapping of information in one channel into and adjacent channel. The length of separation between the channels is dependent on the amount of information which is to be transmitted within the channel. In CDMA, this is 1,250 kHz.
• Modulation—Modulation is the process of sending a signal by changing the characteristics of a carrier frequency. This is done in CDMA via QPSK.
• Transmission rate—This is the amount of information transmitted over a channel over a period of time. CDMA is a digital system with an over-the-air bit rate of about144kbps for 1x, 384-2.4Mbps for 1x EV-DO and 4.8Mbps for 1x EV-DV.
• Capacity and Frequency Re-use —Capacity is the number of frequencies that determines the cell’s capacity. Each company with a license to operate a mobile network is allocated a limited number of frequencies. These are distributed throughout the cells in their network.
Groups of frequencies can be placed together into patterns of cells called clusters. A cluster is a group of cells in which all available frequencies have been used once and only once. Since the same frequencies can be used in neighbouring clusters, interference may become a problem. Therefore, frequency re-use pattern is employed. The frequency re-use patterns ensure that any frequencies being re-used are located at a sufficient distance apart to ensure that there is little interference between them. However, to maximize capacity the frequency re-use distance should be kept as low as possible.


Fig10. A Frequency Re-use Pattern
• Access method—CDMA utilizes the code division multiple access concept. It is a technique which gives a unique code to each call and spreads it over the available frequencies.
3.3.2 Cell Site
This contains equipment which communicate directly with the mobile station. There are three distinct contents in a cell-site. They include: the shelter, the tower (mast), the diesel generator.
-The Shelter: This is a small enclosed compartment which houses the indoor equipment including: the Base Transceiver Station(BTS), Indoor Unit of the Radios, the chrome block, the power rectifiers, air conditioners, environmental alarm chest and fire extinguisher.

Fig11a. A closed shelter








Fig11b. A telecommunication tower

The indoor unit (IDU) are connected to the outdoor unit (ODU) and the BTS. They are used for point to point direction. The power rectifier powers the equipment in the site even during power failure. It has backup batteries that can last for hours in case of power failure. The rectifier is equipped with modules that charge the batteries when on alternating current.

Fig11c. An Emerson Power Rectifier

Fig11d. A Radio Indoor Unit
The air conditioners help to cool the shelter and the equipment. The environmental alarm chest helps in detecting any unusual change in environmental conditions. It serves as a multi detector.

Fig11e. Environmental Alarm Chest
-The Tower (mast): A cell-phone tower is typically a steel pole or lattice structure that rises hundreds of feet into the air. It is always projected very tall above buildings and takes a three or four corner shape. It has an average height of 120-140m. It also has a ladder which is used by the riggers for climbing to install and replace faulty equipment. The equipment that are found on the tower include: the Outdoor Unit (ODU) of the radio, the antennae, the Global Positioning system (GPS) and the aviation light. They are connected to the shelter with their cables.
The ODU is an extension of the IDU. It comprises of the transceiver and the diplexer. It is mainly used for point to point direction with other ODUs in nearby cell sites during handover. The antennae help in boosting the RF frequency. The GPS is used in radio coverage measurement with the help of a tool called Test Mobile Systems (TEMS). The aviation light is connected at the top of the tower and is used for identification.
3.3.3 How the Mobile Station (cell phone) works during transmission
A single cell in an analogue system uses one-seventh of the available duplex voice channels. A cell-phone carrier typically gets 832 radio frequencies to use in a city. Each cell phone uses two frequencies per call -- a duplex channel -- so there are typically 395 voice channels per carrier. (The other 42 frequencies are used for control channels). Therefore, each cell has about 56 voice channels available.
In other words, in any cell, 56 people can be talking on their cell phone at one time. With digital transmission methods, the number of available channels increases. For example, a TDMA-based digital system can carry three times as many calls as an analogue system, so each cell has about 168 channels available. Cell phones have low-power transmitters in them. Many cell phones have two signal strengths: 0.6 watts and 3 watts (for comparison, most CB radios transmit at 4 watts). The base station is also transmitting at low power.
The cellular approach requires a large number of base stations in a city of any size. A typical large city can have hundreds of towers. But because so many people are using cell phones, costs remain low per user. Each carrier in each city also runs one central office called the Mobile Service Switching Centre (MSC). This office handles all of the phone connections to the normal land-based phone system, and controls all of the base stations in the region.
All cell phones have special codes associated with them. These codes are used to identify the phone, the phone's owner and the service provider. These codes include:
- Electronic Serial Number (ESN) - a unique 32-bit number programmed into the phone when it is manufactured.
- Mobile Identification Number (MIN) - a 10-digit number derived from your phone's number.
- System Identification Code (SID) - a unique 5-digit number that is assigned to each carrier by the FCC.
Let's say you have a cell phone, you turn it on and someone tries to call you. Here is what happens to the call:
• When you first power up the phone, it listens for an SID (see sidebar) on the control channel. The control channel is a special frequency that the phone and base station use to talk to one another about things like call set-up and channel changing. If the phone cannot find any control channels to listen to, it knows it is out of range and displays a "no service" message.
• When it receives the SID, the phone compares it to the SID programmed into the phone. If the SIDs match, the phone knows that the cell it is communicating with is part of its home system.
• Along with the SID, the phone also transmits a registration request, and the MSC keeps track of your phone's location in a database -- this way, the MSC knows which cell you are in when it wants to ring your phone.
• The MSC gets the call, and it tries to find you. It looks in its database to see which cell you are in.
• The MSC picks a frequency pair that your phone will use in that cell to take the call.
• The MSC communicates with your phone over the control channel to tell it which frequencies to use, and once your phone and the tower switch on those frequencies, the call is connected. You are talking by two-way radio to a friend!
• As you move toward the edge of your cell, your cell's base station notes that your signal strength is diminishing. Meanwhile, the base station in the cell you are moving toward (which is listening and measuring signal strength on all frequencies, not just its own one-seventh) sees your phone's signal strength increasing. The two base stations coordinate with each other through the MSC, and at some point, your phone gets a signal on a control channel telling it to change frequencies. This hand off switches your phone to the new cell. As you travel, the signal is passed from cell to cell which results in roaming.
Roaming: If the SID on the control channel does not match the SID programmed into your phone, then the phone knows it is roaming. The MSC of the cell that you are roaming in contacts the MSC of your home system, which then checks its database to confirm that the SID of the phone you are using is valid. Your home system verifies your phone to the local MSC, which then tracks your phone as you move through its cells. And the amazing thing is that all of this happens within seconds. Here is a summary of what happens in an outgoing and incoming call and handovers.

Fig12a. Outgoing Call




Fig12b. Incoming Call

3.4 CDMA Subscriber Services
There are two basic types of services offered through CDMA: telephony (also referred to as teleservices) and data (also referred to as bearer services). Telephony services are mainly voice services that provide subscribers with the complete capability (including necessary terminal equipment) to communicate with other subscribers. Data services provide the capacity necessary to transmit appropriate data signals between two access points creating an interface to the network. In addition to normal telephony and emergency calling, the following subscriber services are supported by GSM: facsimile group III, short message services, cell broadcast, voicemail, fax mail, e.t.c.
Other supplementary services include: call forwarding, barring of outgoing and incoming calls, advice of charge (AOC), call hold, call waiting, multiparty service and call line identification presentation/restriction, e.t.c.

CHAPTER FOUR
BASE STATION SUBSYSTEM (BSS)
4.1 INTRODUCTION
The mobile communication system has experienced the first generation (analogue system) and the second generation (digital system). As one of the main development trends of the second generation, the Code Division Multiple Access 1X (CDMA 1X) technology, advocated by the 3rd Generation Partnership Project 2 (3GPP2), has been widely used for commercial purpose.
The Huawei CDMA 1X mobile communication system comprises the Base Station Subsystem (BSS) and the Core Network (CN). Users can operate and maintain the system through an integrated mobile network management system.










Fig13. Network structure of Huawei CDMA 1X system

The BSS consists of the BTS, Base Station Controller (BSC), and Packet Control Function (PCF). The PCF is usually integrated with the BSC. The ODU3601C, a soft site, is also a part of the Huawei BSS.
4.2 BASE STATION CONTROLLER (BSC)
The BSC performs the following functions: BTS control and management, call connection and disconnection, mobility management, power control, radio resource management, provision of stable and reliable radio connections for the upper-level services through soft/hard handoff.
The PCF manages the Radio-Packet (R-P) connection. As radio resources are limited, they should be released when subscribers are not sending or receiving information. But the Peer-Peer Protocol (PPP) connection must be maintained.
Rack Distribution
Large capacity BSC is divided into following functional blocks. In general each block corresponds to single subrack. These are:
 CDMA Switch Subrack (CSWS)
 CDMA Integrated Processing Subrack (CIPS)
 CDMA Resource and Packet Subrack (CRPS)
 CDMA Packet Module Subrack (CPMS)
 Clock processing Module (CLKM)
 CDMA Integrated Management System (CIMS)


Fig14. Rack Distribution
Configuration for 200,000 Voice Subscribers and 400 M Data Throughput
 Busy hour call attempts (BHCA): 600,000
 Voice traffic volume: 6,000 Erl
 Number of voice subscribers (0.03Erl/sub): 200,000
 Number of channels at Um interface: 13,500TCE
 Number of E1/T1 ports at A-interface: 320
 Number of E1/T1 ports at Abis interface: 576
 Number of 1X carriers: 960
 Number of 1xEV-DO carriers: 768
 Number of packet data service PPP connections: 240,000
 Number of packet data service active PPP connections: 10,000
 Total flow of packet data: 400 Mbps
 Traffic of circuit data services: 237Erl
 Number of circuit data service subscribers (0.03Erl/sub): 7,900

4.3 BASE TRANSCEIVER STATION (BTS)
The BTS transmits and receives radio signals to enable the communication between the radio network system and the Mobile Station (MS). Huawei provides a series of BTS products, including: cBTS3612, BTS3606, BTS3612A, BTS3612A and ODU3601C. The most conversant one BTS3606 though the BTS3606E is now in use. The BTS3606 is located between the BSC and the MS in the CDMA 1X system. Under the control of the BSC, the BTS3606 is the radio transceiver equipment serving one cell or multiple logical sectors.
4.3.1 System Overview
-Technical Features: Supports both the CDMA2000 1X and 1xEV-DO standards. Supports CDMA2000 1X / 1xEV-DO hybrid networking. The ratio of CDMA2000 1X and CDMA2000 1xEV-DO carriers is flexible. Support high-power coverage and large-capacity coverage using carriers of different frequencies for a single sector. Support the mixed insertion of different-band carriers in the same cabinet. The BTS3606 can be cascaded with the ODU3601C to expand the coverage area of radio network flexibly. It can support bands of 450 MHz, 800 MHz, and 1900 MHz. The maximum average transmit power is 25 W. After the high-power combiner is configured, the maximum average transmit power can reach 50 W. The main/diversity receiving technology is employed to optimize the receiving performance.
The BTS3606 supports the networking by using E1 and T1 links, and the interfaces of
Inverse Multiplexing for ATM (IMA) and User Network Interface (UNI), The BTS3606 supports networking modes in chain, star, and tree topologies. The BTS3606 supports the following clock sources: Global Position System (GPS) clock, Global Navigation Satellite System (GLONASS) clock and other external clock sources.
-Convenient Operation and Maintenance:
Users can operate and maintain the BTS3606 through the Local Maintenance Terminal (LMT) and the M2000 integrated maintenance console. The following lists the maintenance functions:
a) System status monitoring: This function provides the indication for the system running status and resource status, the configuration of local cell and logical cell, and their status indication. It can also be used to check for the MPP link and the E1 availability using the RJ45 cable.
b) Data configuration: The BTS3606 adopts dynamic data configuration mode. The configured data takes effect without resetting BTS. It also supports the batch processing of data configuration, which allows the configuration of multiple network elements sharing the same attributes at a time.
c) Alarm Processing: This function covers: alarm collection, alarm clearing, alarm querying, alarm shielding, and alarm filtering.
d) Security Management: The security management functions include: User login authentication, Command authority restriction, Confirmation of crucial operation, User group management, Timeout locking.
e) Site monitoring: Data transmission channels are available for the monitoring equipment in the equipment room to facilitate attendance-free and centralized monitoring of the BTS3606.
f) Upgrade: Users can upgrade the system through remote loading. The upgrade process is retrievable, that is, the system can fall back to the original one when the upgrade fails.
g) Equipment operation and auto re-start.


4.3.2 System Structure:
-BTS3606 Specifications

-Cabinet Configuration:
The BTS3606 cabinet is configured with CDDU, combined subrack, power supply subrack, switch box, fan box, cable trough, and tool kit. The combined subrack is designed for installing CTRM/CHPA and baseband boards. The maximum capacity of a single BTS3606 cabinet is two carriers and three sectors, as shown in Fig15

Fig15. BTS3606 Cabinet


Fig15b. BTS3606 Cabinet (Symmetric View)

-Structure:
The BTS3606 system consists of baseband subsystem, Radio Frequency (RF) subsystem, power supply subsystem, and antenna and feeder subsystem, as shown in Fig. 16 below.







Fig16. BTS3606 System Structure


a) Baseband Subsystem: The baseband subsystem comprises the BCKM, the BCIM, and the CCPM.



Fig17. BTS3606 Baseband Subsystem
BCKM: BTS Control and Clock Module, BCIM:BTS Control Interface Module, CCPM:Compact-BTS Channel Process Module.
BCKM’s functions include: Call procedure control, Signalling processing, Resource management, Channel management, Cell configuration.
BCIM’s functions include: Providing multiple E1/T1 links, realizing the IMA/UNI protocol, Support ATM over Fractional E1/T1, Support 8E1.
CCPM’s functions include: In the forward direction, the CCPM completes the following functions: Encoding (including convolution code and turbo code) Interleaving, Spreading, Modulating, and Data multiplexing. In the reverse direction, the CCPM completes the following functions: Decoding, De-interleaving, De-spreading, Demodulating, Data demultiplexing. The CCPM also Connect to ODU3601C by optical port.
b) Radio Frequency Subsystem: The RF subsystem consists of the CTRM, the CHPA, the CDDU, and the CPCM.
CPCM’s functions include: Combine two high-power RF signals and performing backplane transfer of the CHPA alarm signals.
CDDU’s functions include: Provide duplex isolator and low band filter for two receiving and transmitting signals and Testing the coupling of transmitting and receiving signals.
CHPA’s functions include: RF power amplification, Over-temperature alarm, Over-excited alarm and Gain decrease alarm.

Fig18. BTS3606 RF Subsystem
CTRM’s functions include: In the reverse link, the CTRM receives the main and diversity RF signals from the antenna and feeder subsystem, and then changes them into baseband signals through down conversion, wave filtering and multiplexing. Finally the CTRM sends the baseband signals to the baseband subsystem. In the forward link, the CTRM receives the baseband signals from the baseband subsystem, and then changes them into RF signals through de-multiplexing, wave filtering and up conversion. Finally the CTRM sends the RF signals to the RF subsystem through the CDDU.
c) Antenna and Feeder Subsystem: The antenna and feeder subsystem of the BTS3606 includes two parts: the RF part and the satellite synchronization part.
- RF antenna and feeder: This part covers the transmitting and receiving antennas, and feeders. It transmits and receives signals on the air interface.
- Satellite synchronization antenna and feeder: This part includes the satellite signal receiving antenna, feeder, and lightning arrester. It receives synchronization signals from the satellites (GPS or GLONASS) to provide precise clock source for the BTS.
d) Power Supply Subsystem: Subsystem uses three PSUs in full configuration. The PSUs work in the 2+1 redundancy mode. Can use -48V dc input or +24 v DC input. Input voltage: -40VDC~-60VDC(only-48V input OUT voltage: +27V).
CHAPTER FIVE
RADIO UNIT AND ALARM MANAGEMENT
5.1 INTRODUCTION
The radio unit is found inside the shelter with the BTS. The radio model mostly used in Starcomm’s site is NERA Evolution Radio. The Evolution Series microwave radio is designed to transmit data rates from about 6 Mb/s to 600Mb/s, in the frequency bands 5 GHz to 38 GHz. The configuration of capacity and modulation is software configurable, giving an optimal balance between system gain and spectral efficiency. Available interfaces are: E1, T1, E3, DS3, STM-1/OC-3, STM-4/OC12, 100BASE-TX, Gigabit Ethernet. The Evolution Series products can be configured in two different modes, selected by the SW license namely: the METRO mode and the XPAND mode (ETSI).
5.2 FEATURES
The Evolution Series products can be configured in two different modes, selected by the SW license. The Universal IFU can easily be expanded from a single channel system up to a traffic node handling up to 8 ODUs. The Universal IFU contains the line interface, baseband processing and multiplexing, management and radio interfaces. The Universal IFU can easily be expanded from a single channel system up to a traffic node handling up to 8 ODUs. The Universal IFU contains the line interface, baseband processing and multiplexing, management and radio interfaces. The equipment configuration licences and the operating software version can be stored on the memory key available for plug-in, at the front of the equipment or downloaded to a computer. When a new Supervisory Unit is inserted, the equipment configuration can then easily be restored to the radio equipment.
5.3 SYSTEM DESCRIPTION
The Evolution Series microwave radio system comprises an indoor part (Universal IFU), and an outdoor unit (ODU) and an antenna. The
Universal IFU and ODU are interconnected using a coaxial cable which carries the transmit and receive user traffic, management communication between the Universal IFU and ODU, and the power supply to the ODU. In protected configurations, two cables are used; one for each ODU.
a) Interface Unit Description: The Evolution Series Universal IFU is a 1RU high modular unit, containing 9 plug-in slots for various modules. The modular architecture with plug-in slots enables a high degree of flexibility, easy upgrading/changing configurations and maintenance.



Fig19. Interface Unit
The Universal IFU Basic Frame is common in all configurations and up to four IFU frames can be stacked together by an IFU connection panel.
-When an SU is part of the IFU frame, it will always occupy slot 1. The Supervisory Unit is handling the configuration of all the system units as well as reporting system status to the NMS system.
-Slot 9 houses the FAN unit, handling the ventilation and temperature management of the IFU frame.
-Slot 2and 3 house the various user traffic interfaces and optional DXC unit. The PDH and Ethernet traffic interfaces are full height and cover the upper Aux/Serv. position as well.
-Slot 4 and 5 house the RIU unit(s). The RIU unit provides connection to the ODU and supplies power to the IFU Basic Frame with plug-in units and the ODU. If the DXC unit is used, slot 4 and 5 can be used for traffic interfaces as well.
-Slot 7-9 house any Auxiliary or Service Channel units, such as Alarm Unit, Wayside Traffic Unit, 64 kb/s Data Channels unit and EOW unit.
b) Outdoor Unit Description: The ODU hardware is capacity and modulation independent. It consists of a transceiver and a diplexer. The transceiver is tuneable over the whole frequency band, both high and low part. The diplexer determines the sub-band coverage. The ODU may be mounted directly to the
antenna. In HSB and 1+1/2+0 configurations an RF-coupler is used when connecting the ODUs to a single antenna interface. A pole mount interface is also available.
The ODU is made up of the diplexer and the transceiver joined together.



Transceiver Diplexer





ODU ODU identification label placed opposite side of Diplexer identification label
Fig20. ODU and its component parts

Configuration Examples: The Evolution Series equipment can be arranged in various system configurations by means of plug-in units and software licensing. The examples below show systems without the optional AUX plug-in units.
The different examples include:
METRO
1+0 (Unprotected)
1+0 Add-Drop Repeater w/Cross Connect
1+1 (Hot Standby)
1+1 (Hot Standby) - Dual Baseband
1+1 (Hot Standby) - Dual Antenna/Space Diversity
1+1 Frequency Diversity
1+1 Frequency Diversity - Dual Polarization
2+0 Dual Frequency - Single Polarization (DF-SP)
2+0 Single Frequency - Dual Polarization (SF-DP/CCDP)

XPAND
1+0 (Unprotected)
1+1 (Hot Standby)
1+1 (Hot Standby) - Dual Antenna/Space Diversity
1+1 Frequency Diversity
1+1 Frequency Diversity - Dual Polarization














Fig21. Different configuration of the ODU with the antenna



5.4 ALARM MANAGEMENT
It is important to find the defective unit in order to minimize time consumption for fault finding and traffic downtime. This is normally done based on alarms, meter readings and looping from Evolution Manager. The fault-
finding needs to be performed by skilled engineers. Positional problems are also related to installation of IFU-ODU cables and connectors. Alarms can be noticed at the front panel of the IFU. A red LED indicates alarm status on the unit. A blinking red LED indicates that the specific unit is placed in wrong slot according to "Unit Housekeeping". The alarm status can also be monitored from the Evolution Manager, Fault page. It is done by logging in to the radio through the computer with an RJ 45 cable and putting in the correct i.p address.
The most conversant alarms usually encountered in the IFU include: Alarm Indicator Signal (AIS), Loss Factor Signal (LSF), Remote End Fault (REF), Loss Of Contact (LOC), Link Failure, Tx low and high, Rx low and high, Configuration failure, High Bit Error Ratio (HBER), Low Bit Error ratio (LBER), ODU power failure, DEMOD Sync Loss, RF Input Loss, e.t.c.
Each is solved with strict observation and troubleshooting. At times it might lead to changing one or more of the IFU components or even the ODU. The ODU can also be aligned if need be to solve a problem. All replacements should be done with care.
5.5 TRANSMISSION PROBLEMS AND SOLUTIONS
Even as transmission goes on in mobile telecommunication, transmission problems are also encountered which lead to interference and call drops. Some of the problems encountered include:
Path Loss:
Path loss occurs when the received signal becomes weaker and weaker due to increasing distance between MS and BTS, even if there are no obstacles between the transmitting (Tx) and receiving (Rx) antenna. The path loss problem seldom leads to a dropped call because before the problem becomes extreme, a new transmission path is established via another BTS.
Shadowing:
Shadowing occurs when there are physical obstacles including hills and buildings between the BTS and the MS. The obstacles create a shadowing effect which can decrease the received signal strength.
When the MS moves, the signal strength fluctuates depending on the obstacles between the MS and BTS. A signal influenced by fading varies in signal strength. Drops in strength are called fading dips.
Rayleigh Fading:
This occurs when a signal takes more than one path between the MS and BTS antennas. In this case, the signal is not received on a line of sight path directly from the Tx antenna. Rather, it is reflected off buildings, for example, and is received from several different indirect paths. Rayleigh fading occurs when the obstacles are close to the receiving antenna. The received signal is the sum of many identical signals that differ only in phase (and to some extent amplitude). A fading dip and the time that elapses between two fading dips depend on both the speed of the MS and the transmitting frequency.
Time Dispersion:
Time dispersion is another problem relating to multiple paths to the antenna of either an MS or BTS. However, in contrast to Rayleigh fading, the reflected signal comes from an object far away from the Rx antenna. Time dispersion causes Inter-Symbol Interference (ISI) where consecutive symbols (bits) interfere with each other making it difficult for the receiver to determine which symbol is the correct one. An example of this is shown in the figure below where the sequence 1, 0 is sent from the BTS. If the reflected signal arrives one bit time after the direct signal, then the receiver detects a 1 from the reflected wave at the same time it detects a 0 from the direct wave. The symbol 1 interferes with the symbol 0 and the MS does not know which one is correct.
Time Alignment:
Each MS on a call is allocated a time slot on a TDMA frame. This is an amount of time during which the MS transmits information to the BTS. The information must also arrive at the BTS within that time slot. The time alignment problem occurs when part of the information transmitted by an MS does not arrive within the allocated time slot. Instead, that part may arrive during the next time slot, and may interfere with information from another MS using that other time slot. A large distance between the MS and the BTS causes time alignment. Effectively, the signal cannot travel over the large distance within the given time.
Solutions





CONCLUSION
During the course of the Industrial Training Program, I was able to achieve some of the objectives of the Students Industrial Work Experience Scheme (SIWES) programme. During the two months Industrial Training Programme, I was able to put into practice and observe some of the theoretical knowledge provided by the academic studies in the University.
I got to know the inevitability of mobile telecommunications and its numerous services in our daily activities. I got acquainted with network structure of Starcomms CDMA network. I was involved in alarm and traffic management. I learnt a great deal on the installation, maintenance, upgrade and repair of some of the equipment used in transmission.
The SIWES programme should be continued since through it, the students gain a lot of experience in terms of industrial activities and are better equipped to grapple with the challenges of the outside world. The knowledge so acquired from the SIWES programme will be of immense benefit to students in their various fields and career aspiration.