i

Preface

This is report about three months Industrial Training session at ITSMS PVT Ltd,

Malabe. Training report is related with the BTEC HND in Electrical & Electronic

Engineering at ICBT Campus, Mount Lavinia. This report included details of training

establishment, company overview, and services provided by the company in the

chapter 1. In chapter 2, trainee’s experiences, works involved, projects done,

individual activities, industrial experiences gained and skills build are included.

Chapter 3 is reserved for the conclusion.

How Industrial training is helped to improve trainee’s attributions and skills is

discussed here with trainee’s experiences. Basically many activities related to the

telecommunication field such as, link planning, link budget calculating, LOS

calculation, field surveys, link installations, software and hardware upgrading are

discussed here clearly with well-structured manner

ii

Acknowledgement

First of all I would like to pay my gratitude and sincerity to my parents. I am in this

position thanks to their striving effort where they try to make my future a success.

I would like to thank the All the lecturers of Electrical & Electronic section

especially, Mr. Ruwan Fernando for his great contribution in following my training

session as well.

Special thanks to the Project Manager of the ITSMS Engineering division Mr. E.W

Disanayake and General Manager Eng. Nuwan Anuradha for welcoming us to the

company and guiding me throughout the project and for his sincere dedication to

grant us a good training at the division. Special thanks to Mr. Roshan Beliketimulla,

(Manager - Finance). Thank you very much for your kind cooperation.

I offer my special thanks to all the Engineers, technical officers and other staff who

has contributed to make our training a success.

In addition, I must thank all trainees for their wonderful corporation & understanding

during the training.

Thank you.

iii

Table of Content

Preface ......................................................................................................................... i

Acknowledgement ...................................................................................................... ii

Table of Content ....................................................................................................... iii

Table of figures ......................................................................................................... iv

CHAPTER 1 .................................................................................................................. 1

Introduction to the Training Establishment ................................................................ 1

1.1 Introduction ...................................................................................................... 1

1.2 ITSMS Vision & Mission ................................................................................. 2

1.3 Services ............................................................................................................. 2

CHAPTER 2 .................................................................................................................. 9

Training Experiences ..................................................................................................... 9

Establishing a new link .............................................................................................. 9

Mobile Site Planning .............................................................................................. 9

OUTDOOR UNITS .............................................................................................. 15

INDOOR UNITS .................................................................................................. 24

Radio Base Station................................................................................................ 27

RTN600 series upgrading......................................................................................... 29

CHAPTER 3 ................................................................................................................ 34

Conclusion ................................................................................................................... 34

Abbreviations ........................................................................................................... 36

References ................................................................................................................ 38

iv

Table of figures

Figure 1. 1: Weblct2000 screenshot for link configuration ........................................... 3

Figure 1. 2: Training Establishment............................................................................... 5

Figure 1. 3: At the top of Lanka bell tower, Seeduwa ................................................... 6

Figure 1. 4: While testing 1.2m Microwave antenna connections ................................. 6

Figure 1. 5: While setting RRU (Remote Radio Unit)................................................... 7

Figure 1. 6: At a Link installation .................................................................................. 7

Figure 2. 1: Line of sight phenomena .......................................................................... 10

Figure 2. 2: A guy tower .............................................................................................. 13

Figure 2. 3: 30m Mobile tower .................................................................................... 14

Figure 2. 4: A Remote Radio Unit (RRU) ................................................................... 16

Figure 2. 5: 0.6m Microwave antenna ......................................................................... 17

Figure 2. 6: Microwave antenna with ODU................................................................. 18

Figure 2. 7: Antenna bracket with angle indicator. ...................................................... 21

Figure 2. 8: A single Band Antenna............................................................................. 22

Figure 2. 9: A dual band antenna ................................................................................. 23

Figure 2. 10: A DUDU in BTS .................................................................................... 26

Figure 2. 11: Two Alcatel BTSs for GSM and DCS. .................................................. 28

Figure 2. 12Screen shot of WebLct starting page ........................................................ 30

Figure 2. 13NE attribute of a link ................................................................................ 31

Figure 2. 14: Link power level, bandwidth, frequencies indicating in weblct............. 31

Figure 2. 15: Physical board architecture of RTN620 ................................................. 33

1

CHAPTER 1

Introduction to the Training Establishment

1.1 Introduction Integrated Telecom System Management Services Private Ltd has emerged about

three years ago as a Telecom System implementation Contractor for providing high

performance system integrating solutions that meet its Clients specific requirements.

It’s a pioneer telecommunication company in Sri Lanka, Dealing with all

Telecommunication Service Providers in Sri Lanka and Worldwide

Telecommunications vendors such as Ericsson, Huawei, Alacatel, ZTE, etc.

In considering mission of the company, basically dealings are done with

telecommunication vendors such as Ericsson, Huawei and ZTE. Telecommunication

services providers ask vendors to have telecommunication services and fix day today

problems. Then vendors allow ITSMS to do that services and fix problems.

ITSMS Head branch is situated at Malabe, Sri Lanka. Company consist with three

head engineers, two project managers, twenty one technical officers, seven CAD

designers and more than seventy technicians in engineering Division of Malabe

Branch. Furthermore there are branches at Anuradhapura, Galle also to provide island

wide service.

2

1.2 ITSMS Vision & Mission

Vision

To focus be the customer’s first choice and provide services with no setback with

commitment to deliver significant cost & deadline reduction.

Mission

To provide combined expertise with most efficient & reliable services to Telecom

sector with the high ethical standards in timely and professional manner to all our

stake holders in Sri Lanka and other grid-deficit countries.

1.3 Services

ITSMS committed to 100% Client satisfaction and to implement quality integrated

solutions, while deliberately seeking new and innovative ways to develop the talent

and quality of services provided and solve telecommunication installation

requirements with efficient & reliable services with followings.

Preliminary Network Planning Assistance.

Associate with ISPs and plan new network or enlarge networks to have wide

coverage. Basically consider what are the frequencies other services providers are

using and there coverage diameter. This will be discussed widely in next chapter.

LOS & Field Surveys.

Line of sight and field surveys is another service done by ITSMS. Before link

installing available required power level is calculated in networking planning

using “Budgetlink” theory. U2000WebLct software can display actual dbm of that

link in given node.

3

Figure 1. 1: Weblct2000 screenshot for link configuration

Map Analyses.

BTS & MW Equipment Deployment & Commissioning.

Core Network Equipment Deployment. (MSC, BSC, NGN).

Optical Network Termination Equipment Deployment & Commissioning.

Broadband Communication Equipment Deployment.

Installation of Broadcasting Transmitters & Antenna systems.

Equipment Maintenance Management.

Drive Tests.

Network and equipment software updating.

4

Corporate Office

No: 903/D, Udawatta Road,

Malabe, Sri Lanka

Telephone: +94 11 4870284-5, +94 11 2762055

Fax: + 94 11 4542775

Email: admin@aatesl.com

5

Figure 1. 2: Training Establishment

6

Figure 1. 3: At the top of Lanka bell tower, Seeduwa

Figure 1. 4: While testing 1.2m Microwave antenna connections

7

Figure 1. 5: While setting RRU (Remote Radio Unit)

Figure 1. 6: At a Link installation

8

9

CHAPTER 2

Training Experiences

Establishing a new link

Mobile Site Planning

As RND section responsible for the radio network between mobile stations to radio

base station. From RBS to switch path is maintained by transmission section. Then it

is obvious that they must be connected to the switch to work the network.

Transmission people do this job. Their work can be classified as follows.

Planning new links.

Implementing new links.

Maintaining existing links.

Planning new links

For this the suitable path should be found and the parameters of the link should be

checked for required levels. This is done using different analyzing methods and

instruments. When planning a microwave link, between two sites, there are several

aspects to be considered. Out of these factors the most important factor is the

obstruction free path between the relevant points. It is termed as "Line Of Sight". So,

the first factor of a microwave link is the LOS. An optical line of sight exists if an

imaginary straight line can be drawn connecting the antennas on either side of the

link.

10

Figure 2. 1: Line of sight phenomena (1)

Usually “Drive test” activity is used to find out best place to establish a new site. GPS

technology is used at there.

TEMS LINK PLANNER

This is the software used in link planning. This is an Ericsson product. According to

our requirements we can plan the link in this software and we can find out the

availability and performance of that according to the predefined performance

criteria's fed in to the software.

TEMS Link Planner uses a digital map database of Sri Lanka which is in Geobox

format (Geobox format is an Ericsson internally developed format). This map has

very high resolution is rich with all the geographical information of Sri Lanka.

It contains information such as,

Over view/ key map.

Elevation.

Land usage.

Main roads and other roads.

Rivers and Lakes.

On TEMS link planner we can define different map version to help us and to protect

our work, there are map versions such as training version which use for training

purposes, stage 1 ,2 and 3 versions which represents links Mobitel's different projects.

It is very easy to design a TX link using TEMS Link Planner. In order to design a link

first we have to select a proper map version and we must import necessary data to that

map such as height data, Land usage, and existing sites. Then we can implement the

11

link by selecting the two end position of the link. In order to measure the actual

performance of the path we created we have to define several parameters and

configure the path.

Drive test is usually done before planning a link. GPS technology is utilized in finding

most suitable places to establish mobile towers in this task. Especially few needs

consider before establishing a tower. That place must be perfect in financial and

performance sections. Especially in performance. Easy transport is also considered.

Field surveys are as one step of planning new links. If use old tower related to

different provider or have to add another band link (3G or 4G), have to measure the

tower, tower land, numbers of sectors and numbers of antennas and their angle and

height from earth level. If there are any losses or damages of faults those also to be

analyzed in surveys. Additionally, map the entire system devices with its dimensions

with indoor units. That survey report is transferred to vendor to have the approval.

Calculation

In calculating a link, budget link concept is used. Example of microwave link plan is

below.

If Frequency: 2000MHz

Antenna type, station A: P6F-17C height agl. 20m

Antenna type, station B: P6F-17C height agl. 20m

Feeder type, station A: LDF5P50A loss, dB/100m 6.46

Total length, antenna to equipment 30m

Feeder type, station B: LDF5P50A loss, dB/100m 6.46

Total length, antenna to equipment 30m

Path length: 20 km, (therefore clear path loss 124.0 dBi)

12

Obstruction loss: 0.0 dB

Feeder loss, station A: 1.9 dB

Feeder loss, station B: 1.9 dB

Feeder tail loss, total for link: 1.5 dB

Connector loss, total for link: 1.5 dB

Total loss: 130.8 dB

Gain, antenna A: 28.6 dB

Gain, antenna B: 28.6 dB

Total gain: 57.2 dB

Net loss (total loss – total gain): 73.6 dB

Receiver threshold for maximum signal/noise: −125.0 dBW

Design fade margin: +30.0 dB

Design receiver input level: −95.0 dB

(Threshold – fade margin)

Transmitter output power : −21.4 dBW

(Receiver input – net loss)

13

Implementing new links

After planning they try to implement the new link. Normally two teams go to the

implementing process. One team does the job at one side and the other team does their

job at the other side.

Figure 2. 2: A guy tower

Guy towers are places in rural areas because of easy installation and low cost. These

antennas are portable.

14

Figure 2. 3: 30m Mobile tower

15

According to required height, a sufficient mobile tower must be there to place

microwave antennas and sectors and RRUs. In rural areas where, no more links and

technologies, guy towers are used because of easy placement and low cost. Guy

towers are portable ones and can transport entire tower from one place to another

place very easily. Most of the times, usual mobile towers are utilized. Usually, these

towers consist with one or more ladders and platforms and have more safety options

than guy towers.

OUTDOOR UNITS

Microwave antennas (Parabolic dish reflectors), Panel antennas (sector antennas),

RRUs are usually called as outdoor units.

REMOTE RADIO UNIT (RRU)

The radio unit is a microwave radio with RF transceivers, which transmit and receive

RF signals. Traffic signals from the indoor units are processed and converted to

transmitter frequency and sent over the hop.

The radio unit is fitted directly to the antenna as standard. It can also be

installed separately and connected by a flexible waveguide to any antenna with

standard waveguide interface (154 IEC-UBR). It can be disconnected and replaced

without affecting the antenna alignment. There are connections for antenna alignment,

radio cable and grounding. Two LEDs indicate alarm and power on/off. RRU is

responsible for convert light into voltage signal to have better accuracy.

16

Figure 2. 4: A Remote Radio Unit (RRU)

According to bandwidth, RRU is changed. At the beginning there were 2G RRUs

which having mass of 37.5Kg. 3G RRU usually has mass of 23Kg approximately

when 4G RRU is just 13Kg.

17

ANTENNA

Figure 2. 5: 0.6m Microwave antenna

18

:

Figure 2. 6: Microwave antenna with ODU

Five different antenna types, fitting directly to the radio units, are available. 0.2m,

0.3m, 0.6m, 1.2m, and 1.8m are the available compact antennas. All antennas can

also be installed separately and connected to the radio unit by a flexible waveguide. It

is possible to choose between vertical and horizontal polarization. The antenna is

fitted on an antenna support and does not have to be removed during maintenance

after alignment. These antennas are work as both transmitter and receiver

(Transceiver).

These type antennas are called as “Parabolic dish reflectors” usually. Dish is covered

with a leather to avoid from weather effects. Parabolic reflectors typically have a very

high gain like 30-40 dB and low cross polarization. They also have a reasonable

bandwidth, with the fractional bandwidth being at least 5 percent on commercially

available models, and can be very wideband in the case of huge dishes from 0.3m to

19

4.6 meters commonly. Responsible from 150MHZ to 1.5GHZ frequency range.

Frequency range is varying according to model and producer. As an example, smaller

dish antennas typically operate somewhere between 2 and 28 GHz. The large dishes

can operate in the VHF region (30-300 MHz), but typically need to be extremely large

at this operating band.

MAINTAINING EXISTING LINKS

When the network grows up traffic demand get also increase. Also the new

technologies come to the market and company uses those new technologies then

existing links must update. The fault recovery of existing links has done by

transmission section.

First Sector antennas are placed on the tower. Then it’s connected to the RRU through

coaxial cable called “jumper”. Whatever small voltage generated in the sector is

comes to RRU and then converted it to a light signal. Fiber optic cables used to

connect Base band Unit (BBU). Then that light signal is again converted to voltage

signal. In data transmitting E1 standard cable is used in Sri Lanka according European

Standard. E1 cables usually as eight pairs. E1 cables can connected to delivery ports

called as Crones. By crones that signal may be linked with another link also. Suppose

if Galle – Matara link can be connected with Colombo- Galle link using E1 cables at

Galle. Then Matara can connect with Colombo Directly.

Then as an outdoor unit, Antennas or dishes are placed. Towers are connected

through these antennas. Every tower must be linked in a network to have island wide

coverage. Parabolic dishes connect links through microwaves. Dish antennas is

connected with ODU.

ODU is connected with antenna. ODU converts data from the IDU into an RF signal

for transmission. It also converts the RF signal from the far end to suitable data to

transmit to the IDU. ODUs are weatherproofed units that are mounted on top of a

tower either directly connected to a microwave antenna or connected to it through a

20

wave guide. Here ODUs are full duplex configured. The ODU receives its power

from the IDU through a coaxial cable. ODU parameters are configured and monitored

through the IDU. Each ODU is designed to operate over a predefined frequency band.

For example 21.2 to 23.6GHz for a 23GHz system, 17.7 to 19.7GHz for a 18GHz

system and 24.5 to 26.5GHz for a 26GHz system as for DMC XP4 ODUs. Suitable

ground wire should be connected to the ODU ground lug to an appropriate ground

point on the antenna mounting or tower for lightning protection. It should be noted

that this unit is electronically controlled. Transmitted power is controlled by adjusting

a value on the IDU which instructs the ODU to adjust the drive voltage on its

Transmitter PIN diode attenuator. ODUs are categorized as 1+0, 1+1,2+0 and 2+2.

1+0 means ODU work only with active mode. At 1+1 ODU has standby option also.

SECTOR ANTENNAS

In its base stations Mobitel uses sector antennas (panels ) to provide radio

coverage to the subscribers. These sector antennas normally transmit with a

transmission power around -35 to - 40 db. This power level is adjusted by RBS.

Sector antennas that we use in Mobitel support polarization diversity in order to

increase its receiver sensitivity. In polarization diversity the receiver antenna has two

antenna arrays one with -45º and other with +45º angles. Sometimes, frequency

antennas are used. Dual frequency antennas are capable of operating in two separate

frequency bands. These are used in sites where there is both GSM 900 and GSM 1800

radio base stations are present, so without having two separate antennas there can be

used dual band or tri band antennas. In geometry, a "sector" is a "slice" or "wedge" of

a circle. Picture a slice of a pie being lifted from the pie, and you get a visual image of

a sector. A sector antenna is a directional antenna designed to cover this kind of

geometric shape. There are different types of antenna in considering covering area.

A 60 degree sector antenna covers 60 degrees of a 360 degree circle, while a 90

degree sector antenna covers a fourth of that same circle. The radiation areas don't end

abruptly at 60, 90, or 120 degrees; these have a few degrees of overlap so you could,

21

for example, use three 120 degree sector antennas for full coverage of a circle. In real

world, sector antennas have a range of about 4 to 5 km.

Figure 2. 7: Antenna bracket with angle indicator.

22

Usually, in fitting antennas, the angle is considering much with getting connection

with mobiles. Antenna bracket is used to keep antenna fix and set the required

direction.

Types of antennas

Single Band Antenna

Figure 2. 8: A single Band Antenna

Single band antenna is also called as mono band antennas. By today these antennas

are replaced rapidly because of invention of new technologies and bandwidths. Most

of Mono band antennas are GSM900 ones.

23

Figure 2. 9: A dual band antenna

24

Dual band antennas consists two bandwidths or bands in one antenna. These are more

popular because low space and low maintenance required. Bands are DCS1800, 3G or

GSM900, DCS1800.

INDOOR UNITS

ACCESS MODULE MAGAZINE (AMM)

The AMM houses the plug-in units and is designed for fitting in a 19" rack or cabinet.

There are two types of AMM.

AMM 1U-1 is used for 1+0 terminals and can house one MMU and one TRU.

AMM 2U-4 is mainly used for 1+1 or two 1+0 terminals and can house up to

four units; two MMUs and two TRUs.

The plug-in units are inserted into the AMM from the front. The connection between

plug in units is made through the backplane of the AMM. All indicators and external

connector interfaces are located on the fronts of the plug-in units.

Cables are routed to the left and right hand side of the front. The AMM has a front

panel to protect the cables and connections. Indicators are visible through the front

panel. Tools, used for removal of the plug-in units, are attached to the inside of the

front panel

PLUG-IN UNITS FOR THE AMM

Modem unit (MMU)

The MMU is the indoor interface with the radio unit and contains a modulator and

demodulator. The MMU provides traffics and capacity of 155Mbit/s and is frequency

independent. One MMU per radio unit is required is required.

Traffic Unit (TRU)

The main functions of the TRU is the generating and terminating g an SDH STM-1 or

SONET OC-3 signal and transmit it to or receive it from the MMU. It also contains a

25

protection switching function used for protected terminal configuration. One TRU

per terminal is required. Besides the main traffic (155Mbit/s), there are three

auxiliary channels; one channel for wayside traffic and two service channels. The

TRU comes in two versions; the TRU EL. With electrical traffic interface, and the

TRU EL/OPT with both electrical and optical traffic interfaces

FAN UNIT

To guarantee sufficient cooling for the plug-in units, a fan unit is always fitted on top

of the AMM. One fan unit per AMM is required. The cooling air enters at front of the

AMM, flows between the units and out through openings at the back of the AMM.

DC DISTRIBUTION UNIT (DDU)

The optional Dc distribution unit is used for distribution of primary Dc power

to a maximum of five MMUs or fan units. Each output is protected by an automatic

type fuse (6A) combined with an on/off switch.

26

Figure 2. 10: A DUDU in BTS

After ODU, data goes to IDU through IF cable (Intermediate frequency cable). IDU

contains much of the intelligence of the system. Main functions of the IDU include

Providing the Data interface, Error correction, Modulation and Demodulation, Alarm

status monitoring and Site-to-site communications. An IDU located in an equipment

shelter to interface with the operator interface and is connected to a close coupled

ODU Antenna assembly on the tower by a single coaxial cable. The IDU is

independent of any frequency band and will operate over all frequency ODUs. But it

is capacity dependent and there are separate modules capable of handling different

capacity inputs. Configuring and monitoring of link performance can be done

through the IDU front panel. Display of Local & Remote radios and Alarm Relay

DCDU

BBU MUX

27

Status LEDs are there in the IDU front panel for fault identification. Memory backup

inside the IDU ensures that it maintains its configuration in the event of a DC power

loss.

Radio Base Station In data transmission chapter, maintenance and repairing of radio base stations is also

included. Radio base station (RBS) is the interface between mobile subscriber and the

network. It provides radio coverage to the subscriber through the radio antenna.

Operations department look after radio base station equipment as well as cooling

(AC) units and power supplies used in the base stations. Mobitel Lanka uses

types of RBS equipments they are namely,

RBS 2206

RBS 2207

Both of them are products of Erricsson. There is no significant difference between

these two equipments except for the fact that RBS 2206 and all its related units

operates in GSM 1800 frequency and RBS 2207 and all its related equipments

operates in GSM 900 frequency band. There are some TDMA (Time division multiple

access) radio base stations also used in Mobitel but there are only few sites operates in

TDMA. TDMA is the technology which is used before GSM. Mobitel still has some

customers who are using TDMA, but they are encouraged to migrate to GSM. There

are more brands of BTS in the field as Alcatel- Lucent.

28

Figure 2. 11: Two Alcatel BTSs for GSM and DCS.

29

RTN600 series upgrading

RTN stands for Regional Telecommunication Network. This instrument is made by

Huawei. The OptiX RTN 600 series TDM/hybrid integrated radio transmission

system (OptiX RTN 600 for short) is a digital microwave transmission system for

data packets. The system provides end-to-end transmission from the access layer to

the backbone layer and can work with optical network equipment for end-to-end

service grooming and unified network management. With the evolution from TDM to

IP, IP-based microwave transmission solutions have become a trend. The OptiX RTN

600 helps smooth evolution from TDM microwave transmission to IP-based

microwave transmission, saving network construction and operation costs. The OptiX

RTN 600 is available in two models, the OptiX RTN 620 and the OptiX RTN 605.

RTN responsible in interconnecting links and create internetwork. The sharing

capacity can be increased by changing modulation way and number of E1 cables

connected with RTN. In doing that operation RTN is upgraded in both hardware and

software sections.

In working with Huawei RTN, there was as standard software named, U2000WebLct

implemented by Huawei technologies. U2000WebLct installed PC or Laptop must be

connected with RTN through Ethernet cable to connect with RTN. Internet explorer is

associated with WebLct.

30

Figure 2. 12Screen shot of WebLct starting page

31

After log with the link, weblct shows link ID, link IP address, link name, extended ID

with the far end tower also.

Figure 2. 13NE attribute of a link

It always shows far end tower and its details as follows.

Figure 2. 14: Link power level, bandwidth, frequencies indicating in weblct

32

The air interface of the OptiX RTN 620 supports 7MHz to 56MHz channel bandwidth

and QPSK to 256 QAM modulation mode. The TDM air interface is flexibly

configurable from 4E1 to 75E1; while the throughput of native Ethernet service is

flexibly configurable from 10 Mbit/s to 400 Mbit/s. With the design of single-device

multiple RF directions and the networking microwave equipment, the OptiX RTN 620

delivers more flexible ring networking (PDH/SDH-Ring) and full timeslot cross-

connection to any direction is available. Featuring quick service provision and

adjustment, the OptiX RTN 620 decreases the number of DDF racks, external cable

connectors, and IDU service interface units, while omitting the external ADM

equipment.

When the air interface link works properly (for example, in sunny days), a higher

modulation mode is adopted to provide high-bandwidth transmission capabilities

through the adaptive modulation (AM). This helps reduce the capital expenditure

(CAPEX) by making full use of the bandwidth resources. When the quality of the air

interface link degrades (for example, in heavy rain or heavy fog), a lower modulation

mode is adopted to increase the anti-fading capabilities. This guarantees high-quality

data transmission for key users. Making full use of frequency spectrum resources, the

OptiX RTN 620 helps greatly reduce TCO.

Combining cross polarization interference cancellation (XPIC) with the same channel

dual polarization (CCDP) technology under the TDM mode, the OptiX RTN 620

doubles the transmission capacity under the same channel condition. The OptiX RTN

620 boasts sound protection mechanism, which includes 1+1 power protection; 1+1

and N+1 protection in TDM mode configuration; linear multiplex section protection

between optical transmission link and STM-1 link; and two-fiber bi-directional

multiplex section protection ring of the STM-4 optical link. In TDM mode, the OptiX

RTN 620 supports SNCP for E1 services and ERPS protection, that is, hybrid ring for

data services.

33

In upgrading RTN, first hardware upgrading must be done. Usually all the hardware

equipment are shown in software.

Figure 2. 15: Physical board architecture of RTN620

First two units (no.17 and no.15) are not in RTN. Those are in ODU. No.7 and no.5

units are responsible for IF cards. In this RTN there is one IFH1 card and one IFH2

card. Two cards for 1+1 operation as mentioned under ODU topic. No.5 unit is main

IF card. No.7 is the standby IF card. In this operation, no.5 card has been replaced

with IFH2 card. N0.8 slot responsible for the Ethernet card. Before upgrading there’s

no EMS card in the RTN. EMS card is used to develop switching system from

message switching to packet switching.

34

CHAPTER 3

Conclusion

At ITSMS, could follow training period of three months and could gain both

theoretical and practical knowledge also. Telecommunication is a vast area and day

by day new technologies are introduces and job opportunities are generated. In

training period, could involve with many projects of Dialog Telekom and Mobitel

Lanka as installation, surveys, workshops, link configurations, testing (TSWR, LOS,

etc.), Software upgrading (WebLCT 2000 of Huawei), Link planning.

Telecommunication field training session is an adventure and practically builds one

especially. Training establishment (ITSMS Pvt LTD was awarded as the best

constructor in Asia region of Huawei in 2008, 2009 and 2010. Following training at

that kind of place gained accuracy of tasks done, leadership, responsibility also.

ITSMS is well standard mobile constructing company working according to related

rules and regulations. They provide better services for trainees by providing monthly

salary and overtime payments with leaves. They also Provides a good industrial

training both theoretically and practically. To have to work with Qualified Engineers

of world leading telecommunication companies and to have share ideas and get

knowledge is a real benefit a trainee can get who, having industrial training at ITSMS.

ITSMS also provides good transport facilities, accommodation facilities and all the

basic needs such as office wears, food and beverages, training kits in their projects.

If consider about my industrial training at ITSMS as an undergraduate trainee allowed

me to collect uncountable number of experiences about telecommunication field, team

leading, on time working, having responsibilities, industrial fault analysis and solving.

35

Trainings were not indoor always. Majority of practical sessions were done in

outdoors at many places in Sri Lanka such as, Colombo regional area, Gampaha,

Waththala, Biyagama, Seeduwa, Mabola, Anuradhapura, kekirawa, Puththalam,

Mahawilachchiya, Jaffna, Vavuniya, Trinco, Polonnaruwa, Habarana, Kurunegala,

Rathnapura, Galle, Kaluthara,Ampara, Batticaloe, Nelliadi, Nellikulam, Meerigama,

chilaw, Mathale, Raththota, Dummalasuriya, etc. As training works Site drawing, site

surveying, Link power strength calculation, IDU software upgrading, System error

checking, Establishing multiflexers (MUX), Link establishment, 2G,3G and 4G

cutovers, IDU data cards replacement or installing, Drive tests, preparing link

documents and project documents can be included basically. Within Three months

could have good priceless experiences about telecommunication field.

Telecommunication field is not a comfortable field to have many facilities in the

training period or at career level. It’s always associated with the real world and has to

work outdoor with giant responsibilities. Each and every member of the team has big

responsibility in working with a giant network such as keep the network active and

eliminates losses. It’s a nice and adventurers experience to work at different locations

at different times with different responsibilities.

I would like be thankful to All ITSMS staff members especially, Engineering

Division for their great help and guidance in making success may industrial training

period and all other Engineers and technical officers in Mobitel Lanka, Dialog

Telekom and Huawei Sri Lanka who associate with us and encouraged during my

training period.

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Abbreviations

2G: Second Generation.

3G: Third Generation.

4G: Fourth Generation.

AM: Adaptive Modulation.

AMM: Access Module Magazine.

BBU: Base Band Unit.

BTS: Base Transceiver Station.

CAPEX: Capital Expenditure.

DCDU: DC Distribution Unit.

DCS: Digital Cellular System.

DDF: Digital Distribution Frame

EM: Electromagnetic.

FU: frame Unit.

GMSK: Gaussian method Minimum Shift Keying.

GPS: Global Positioning System.

GSM: Global System for Mobile Communication.

IDU: Indoor Unit.

IF: Intermediate Frequency.

IP: Internet Protocol.

ITSMS: Integrated Telecom System Management Services PVT. LTD.

LOS: Line of Sight.

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MMU: Modem Unit.

MSC: Mobile Switching Center.

MW: Micro Wave

NTS: Network transmission System.

ODF: Optical Distribution Unit.

ODU: Outdoor Unit.

PC: Personal Computer

PDH: Pleschronous Digital Hierarchy.

QAM: Quadrature Amplitude Modulation.

QPSK: Quadrature Phase Shift Keying.

RBS: Radio Base Station.

RF: Radio Frequency.

RND: Radio Network Design.

RTN: Radio Transmission Network.

Rx: Receiver.

SDH: Synchronous Digital Hierarchy.

TDMA: Time Division Multiple Access.

VSWR: voltage standing wave Ratio.

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References

Electronic References

Official Web site of A&A Telecom Pvt. Ltd.

A & A Telecommunication Engineering Services (Pvt) Ltd . 2013. A & A

Telecommunication Engineering Services (Pvt) Ltd . [ONLINE] Available

at:http://aatesl.com/Index.htm. [Accessed 21 March 2013].

Figure reference

(1) Weird & Wireless: RF "Line of Sight" (Electro-ramblings). 2013. Weird &

Wireless: RF "Line of Sight" (Electro-ramblings). [ONLINE] Available

at:http://www.electronicsweekly.com/blogs/electronics-weekly-

blog/2009/10/weird-wireless-rf-line-of-sight.html. [Accessed 21 March 2013].

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