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Training report - ITSMS Pvt Ltd.
 

Training report - ITSMS Pvt Ltd.

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Three month training period at ITSMS Pvt Ltd for the completion of BTEC HND in Electrical and Electronic Engineering

Three month training period at ITSMS Pvt Ltd for the completion of BTEC HND in Electrical and Electronic Engineering

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    Training report - ITSMS Pvt Ltd. Training report - ITSMS Pvt Ltd. Document Transcript

    • 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.
    • 36 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.
    • 37 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.
    • 38 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].
    • 39