INTERNSHIP SEMINAR REPORT on EARTH STATION COMPLEX
Work carried out at DOORDARSHAN KENDRA, BENGALURU
Submitted in partial fulfillment of the requirement for the award of Bachelor of Engineering Degree
in Telecommunication Telecommunication Engineering
of Visvesvaraya Visvesvaraya Technological University, Belagavi
by
SHABARISH S.
USN: 1BI15TE039
Under the guidance of Prof. Jamuna M.
Assistant Professor Department of Telecommunication Engineering B.I.T., Bengaluru.
DEPARTMENT OF TELECOMMUNI T ELECOMMUNICATION CATION ENGINEERING
BANGALORE INSTITUTE OF TECHNOLOGY, BENGALURU -560004 2018-2019
BANGALORE INSTITUTE OF TECHNOLOGY K. R. Road, V. V Pura, Bengaluru-560004 Department of Telecommunication Engineering
CERTIFICATE Certified that the Internship Seminar entitled “EARTH STATION COMPLEX” carried out DOORDARSHAN KENDRA, BENGALURU, by SHABARISH S. (USN:1BI15TE039),
bona fide student of Bangalore Institute of Technology in partial fulfillment for the award of Bachelor of Engineering Degree in Telecommunication Telecommunication Engineering of the Visvesvaraya Technological University, Belagavi during the year 2018 -19. It is certified that all
corrections/suggestions indicated for Internal Assessment has been incorporated in the report deposited in the Departmental Library. The Internship Seminar Report has been approved as it satisfies the academic requirements in respect of Internship Work prescribed for the said Degree.
Guide
HOD
Principal
Prof. Jamuna M.
Dr. S. Shanthala
Dr. Aswath M.U.
External Viva: [For Internship only]
Name of the Examiners 1.
2.
Signature with date
ACKNOWLEDGEMENT
It would be our privilege to express my heartfelt gratitude and respect to all those who guided me in the completion of this Internship. I’m highly indebted to Rajya Vokkaligara Sangha trust for introducing a great Educational Institute for studies. I express my deep sense of gratitude to our Principal, Dr. Aswath M. U., for providing an excellent academic environment which enable me to complete the Internship. I would like to express my heartfelt gratitude to Head of Department, Department of Telecommunication Engineering, Dr. S. Shanthala , for her constant support. I would like to express my heartfelt gratitude to my Internship guide, Prof. Jamuna M. , Assistant Professor, Department of Telecommunication Engineering, for her constant support and guidance during the Internship. I would like to express my heartfelt gratitude to Mr. Niranjan, Deputy Director (Engg.), Doordarshan Kendra, Bengaluru, for his constant support and guidance during the
Internship. I would like to express my heartfelt gratitude to t o our Internship Coordinator, Prof. N. Shruthi. , Assistant Professor, Department of Telecommunication Engineering, for her constant support and guidance during the Internship. I’m great full to all the Teaching and Non-Teaching Staff, Department of Telecommunication Engineering, who have been an inspirational support.
ABSTRACT
Interning at Doordarshan Kendra was an opportunity to learn about real time communication systems. In this report, a brief introduction on Doordarshan is given and then a discussion on various television broadcasting systems used in Doordarshan is made. The primary focus in this report is on Earth Station Complex. There are two types of transmission of Doordarshan Channels. One is Terrestrial Transmission and the second one is Satellite Transmission. There are three terrestrial transmitters, transmitt ers, whose properties are discussed in this report. Out of the three, two are analog transmitters and one is digital transmitter. The block diagram of the signal flow of these transmitters are discussed in this report. The main block of the Satellite Transmission is the 2+1 Chain Room. A block diagram of the signal flow in the 2+1 Room is shown and a brief explanation on the same is given in this report. Finally a discussion on DSNG (Digital Satellite News Gathering), which is a mobile earth station used for outside broadcasting is made in this report.
i
TABLE OF CONTENTS SL. NO
TOPIC
PAGE NO.
Acknowledgement Abstract
i
Table of Contents
ii
List of Figures
iii
List of Tables
iv
List of Abbreviations Abbreviations
iv
About the Company
v
1
Objectives
1
2
Introduction
2
3
2.1 Doordarshan
2
2.2 DD Chandana
3
2.3 Different Sections of DDK, Bengaluru
3
Internship Discussion
4
3.1 Terrestrial Transmission
4
3.2 DD1 - DD National
5
DD2 – DD DD News 3.3 DD2 –
6
3.4 Digital Terrestrial Transmission
6
3.4.1 DVB T2
6
3.4.2 Harris 6kW Transmitter
7
3.5 Earth Station
9
3.5.1 2+1 Chain Room
10
3.6 Digital Satellite News Gathering
12
4
Weekly Report
13
5
Conclusion
17
References
18
ii
LIST OF FIGURES
Figure No.
Title
Page No.
2.1
Organization Overview
2
3.1
Overview of Television Transmission
4
3.2
Block Diagram of DD1 Transmitter
5
3.3
Block Diagram of DD2 Transmitter
6
3.4
General Block Diagram of Digital Transmitter
8
3.5
Block Diagram of Harris 6kW DTT
9
3.6
Basic Block Diagram of Earth Station
10
3.7
Block Diagram of 2+1 Room
11
3.8
Typical DSNG Setup (1+1 Configuration)
13
3.9
DSNG Van
13
3.10
TVU Pack Block Diagram
14
iii
LIST OF TABLES Table No.
Name of the Particulars
Page No.
3.1
Satellite Details of Earth Station
12
3.2
DSNG Parameters
14
LIST OF ABBREVIATIONS Abbreviations
Descriptions
AIR
All India Radio
CAR
Central Apparatus Room
CCU
Camera Control Unit
DDK
Doordarshan Kendra
DTT
Digital Terrestrial Transmission
DSNG
Digital Satellite News Gathering
DVB-T2
Digital Video Broadcasting — Broadcasting — Second Second Generation Terrestrial
ENG
Electronic News Gathering
LED
Light Emitting Diode
MCM
Master Control Module
MSR
Master Switching Room
OB
Outdoor Broadcasting
PCM
Processor Control Module
PCR
Production Control Room
VTR
Video Tape Recording
iv
ABOUT THE COMPANY
Doordarshan (DD) is an Indian public service broadcaster, a division of Prasar Bharati. It is one of India’s largest broadcasting organizations organizations in terms of studio and transmitter infrastructure. Recently, it has also started broadcasting on digital terrestrial transmitters. The DD provides television, radio, online and mobile s ervices throughout metropolitan and regional India, as well as overseas through the Indian Network and Radio India. DD Chandana is one of the regional channels of Doordarshan Network, providing programs mainly in Kannada including different dialects and local variations. The first city to have Doordarshan Kendra in Karnataka was Gulbarga. It was opened as a continuity of Satellite Instructional Television Experiment (SITE) on 3 rd November 1979. On 1 st January 2000, the regional channel became a 24 hours channel. The
DDK
Bengaluru
has
young
staff
of
Engineers
guided
by
Mr.
Niranjan,
Deputy Director (Engg.). It was a great opportunity for me to spend time with the staff of Doordarshan Kendra, Bengaluru. I gained immense knowledge by interning here at Doordarshan Kendra Bengaluru.
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1. OBJECTIVES
The objectives of the internship are listed below.
Gain Industrial Exposure
The primary objective of the Internship is to gain industry exposure. As an engineer it is important to gain industrial knowledge, so that real time problems can be analyzed. A knowledge, on what scale engineering concepts learned in a classroo m are being implemented, is obtained.
Learn Basics of Terrestrial Terrestrial and Satellite Transmission Transmission
Learning the basics of terrestrial and satellite transmissi on is the secondary objective of this program. An overview on television broadcasting through terrestrial terrestri al transmitter as television services provided through satellite was given.
Obtain Practical Knowledge
This internship provided an opportunity to experience live examples of the use of signal processing techniques and various digital modulation techniques. Overall, obtaining a practical knowledge on communication concepts concepts is also an objective of the internship.
Develop Professional Skills
One of the objectives of the internship was to develop professional skills. Skills such as leadership, mentoring, conflict resolution, etc. are certain skills which are essential to become a successful person. In In this program, such skills are tacitly conveyed. By spending time around professionals in a work place such skills can be learnt tacitly.
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2. INTRODUCTION 2.1 DOORDARSHAN DOORDARSHAN Doordarshan is a public service broadcaster founded by Government of India and owned by Broadcasting Ministry of India. It is one of the two division of Prasar Bharati. It was initially started as an experiment in Delhi on 14 th September 1959, with a small transmitter and a makeshift studio. Regular transmission started in 1965 with a five minute news bulletin as a part of All India India Radio. Television service was separated from radio on 1st April 1976. In 1982 Doordarshan became a national broadcaster. Prasar Bharati is the parent body of Doordarshan and its board members are appointed by Government of India through the Information and Broadcasting Ministry. It is a statutory autonomous body setup by an Act of Parliament and comprises of the Doordarshan Television Network and All India Radio. An overview of the organization is shown in Figure-1.1. Figure-1.1. Doordarshan operates 35 channels. Out of which 8 all India channels, 11 regional-language satellite channels, 15 state networks, an international channel, a sports channel namely DD sports, and other channels such as DD Bharati, DD Urdu and DD Kisan. Doordarshan has 67 studio centers all over the country, including 17 major studio centers at State capitals, a Regional Production Centre at Guwahati and 49 other studio centers located i n various cities. Doordarshan also provides DTH services.
MINISTRY OF INFORMATION AND BROADCASTING
PRASAR BHARATHI
AKASHVANI
DOORDARSHAN
Figure 2.1: Organization Overview
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2.2 DD CHANDANA DD Chandana is one of the regional channels of Doordarshan Network, providing programs mainly in Kannada including different dialects and local variations. The first city to have Doordarshan Kendra in Karnataka was Gulbarga. It was opened as a continuity of Satellite Instructional Television Experiment (SITE) on 3 rd November 1979. On 1 st January 2000, the regional channel became a 24 hours channel. Doordarshan Kendra, Bengaluru is located on the northern side of the Bangalore city. This Kendra has a studio complex consisting of main studio, continuity studio, Outside Broadcasting Van (OB Van), Electronic News Gathering (ENG) production facility, Satellite Earth Station and a 6KW Digital Terrestrial Transmitter.
2.3 DIFFERENT SECTIONS OF DDK BENGALURU Doordarshan Kendra Bengaluru consists of the following important sections and subsections. The overall functioning of the Doordarshan is embedded in to these sections. They are:
Studio
Studio 1 and Studio 2
Video Tape Recording Room (VTR)
Production Control Room (PCR)
Camera Control Unit (CCU)
Master Switching Room (MSR)
Central Apparatus Room (CAR)
Graphics
Electronic News Gathering (ENG)
Earth Station
Playback Server Room
2+1 Room
Digital Terrestrial Television
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3. INTERNSHIP DISCUSSION 3.1 TERRESTRIAL TRANSMISSION Digital terrestrial television broadcasting allows the transmission of about ten or more digital services in a single frequency channel, whereas analog broadcasting is limited to only one service in one frequency channel. There are three terrestrial transmission services in Doordarshan Kendra, Bengaluru. They are:
DD1 – DD1 – DD DD National
DD2 – DD2 – DD DD News
DTT - 5 Video Channels + 3 Radio Channels
The DD1 and DD2 are analog transmitters. DTT stands for Digital Terrestrial Transmitter. As the name suggests is a digital transmitter. An overview of transmission system in DDK Chandana is given in Figure 3.1.
Figure 3.1: Overview of TV Transmission
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3.2 DD1 – DD DD NATIONAL A block diagram of DD1 transmitter is shown in Figure 3.2. The features of DD1 transmitter are as follows:
DD1 is an Analog Transmitter.
It was manufactured by NEC.
The power of the Transmitter is 10kW.
Transmission occurs in VHF band Channel-5.
The video frequency is 175.25MHz.
The audio frequency is 180.75MHz.
It covers an area of 70km of radii.
As the figure indicates, the audio and video signals are fed to the exciter. There are two exciters in which one acts as a standby. The amplitude modulation is performed on video signal and frequency modulation is performed on audio signal, in the exciter. The signal from the excit ers are then fed to a power amplifier which amplifies the modulated signal. The service hours of DD1 channel are as follows.
5:27Hrs to 6:00Hrs: National Services (DD National)
06:00Hrs to 09:00Hrs: Regional Services (DD Chandana)
09:00Hrs to 15:00Hrs: National Services (DD National)
15:00Hrs to 19:00Hrs: Regional Services (DD Chandana)
19:00Hrs to 00:00Hrs: National Services (DD National)
Antenna Video Audio
V Exciter Circuits (A)
A Exciter
V
Amplifier
Switching Video Audio
Exciter Circuits (B)
V
Circuits
Visual Power
A
Aural Power
V A
Diplexer
Amplifier A
Figure 3.2: Block Diagram of DD1 Transmitter
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3.3 DD2 – DD DD NEWS The features of DD2 transmitter are as follows.
Manufactured by Harris.
It is an analog transmitter.
It works in VHF Band Channel – Channel – 7. 7.
The output power of the transmitter is 1KW.
Video Frequency of the channel is 189.25MHz.
Audio Frequency of the channel is 195.75MHz.
It covers an area of 40km radii.
Its total service hours are 05:58 to 00:30Hrs, which accounts to 18Hrs 32min.
A block diagram of the transmitter is shown in Figure 3.3. Its working is similar to the DD1 transmitter. The output of the exciter is given to an auto gain controller which controls the amplitude of the modulated signal, so that it remains constant. It is then amplifier and fed to the diplexer. The diplexer multiplexes the audio and video signals and then sends to the antenna.3
Antenna Video
Exciter
Audio
Circuits
V
V
AGC
A
A
PA Driver
Exciter
V Diplexer
Switching Video Audio
Exciter
V
A
Circuits
Circuits (B)
A
A
AGC
PA
Figure 3.3: Block Diagram of DD2 Transmitter
3.4 DIGITAL TERRESTRIAL TELEVISION 3.4.1 DVB-T2 There are many DTT broadcasting standards world over, such as Advanced T elevision Systems Committee (ATSC, USA), Digital Terrestrial Multimedia Broadcasting: (DTMB, China), Digital Video Broadcasting-Terrestrial (DVB-T, Europe) and Integrated Services Digital Broadcasting-Terrestrial (ISDB-T, Japan) focus on stationary reception with home TV sets and high-mounted rooftop antennas. Digital Multimedia Broadcasting (DMB), 1-Seg, DVB-H and DVB-T2 Lite are mobile TV standards. Department Department of Telecommunication Telecommunication Engineering, Engineering, B.I.T.
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India has adopted DVB-T2 Standard, which is second generation of DVB and has highest data capacity. The DVB-T2 system is an OFDM-based broadcasting standard used not only for stationary reception, but also for mobile applications. Doordarshan is transmitting all free-to-air channels in analog format since 15th September 1959. It is necessary to migrate to digital terrestrial broadcasting as the world is moving away from analogue to digital broadcasting. Going digital will provide multiple channels, better video and audio quality, provide signals for mobile and portable devices like mobiles, tablets, PC etc. and other value added services, besides it will allow the government to free up frequency spectrum which can be used for new services like mobile, wireless broadband and potentially more TV services and channels. Some advantages of DTT Transmission are as below:
Analog TV (ATV) is subject to t o interference, such as ghosting and snowing, depending on the distance and geographical location of the TV receiving the signal. These interferences are not seen in Digital TV
Digital TV supports Standard Definition TV (SDTV) High Definition TV (HDTV) and Ultra High Definition TV (UHDTV).
DTT Transmitters have been installed in 19 Cities namely - Ahmadabad, Jalandhar, Aurangabad, Kolkata, Bangalore, Lucknow, Bhopal, Mumbai, Chennai, Patna, Cuttack, Raipur, Delhi, Ranchi, Guwahati, Indore, Srinagar, Hyderabad and Thiruvananthapuram. The signal from these Transmitters will be available up to about 60-70kms in all directions in fixed mode and 25-30kms in mobile mode from the TV Tower. In mobile reception there may be some gaps where signal may not be available at present. DTT Services will be expanded to 64 cities in coming days.
3.4.2 HARRIS 6KW TRANSMITTER The properties of the DVB-T2 transmitter used in digital terrestrial transmiss ion are as follows.
It is a digital transmitter.
It is manufactured by Harris.
It works in UHF band channel -24.
Transmission frequency is 498MHz. It has a bandwidth of 8MHz.
Power of the Transmitter is 6kW.
It provides 5 video services namely DD National, DD Sports, DD News, DD Bharati, DD Chandana.
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It also provides three radio services namely AIR Ragam, AIR Kannada, FM Rainbow.
It has a liquid cooling system.
It covers a radius of 50km.
The basic setup of the digital transmitter is shown in Figure 3.3. The block diagram of the transmitter is shown in the Figure 3.4.
Exciter
Power
Pre Driver
Intermediate Power
Unit
Amplifier
Antenna
Combiner
Amplifier
Figure 3.4: General Block Diagram of a Digital Transmitter
As shown in Figure 3.4 the transmitter consists of exciter, pre-driver unit, intermediate power amplifier, power amplifier, combiner and transmitting antenna. Exciter contains elements such as oscillator, modulator and audio processor. It is used to drive the transmitter. The intermediate power amplifiers are used to pre amplify the signals. The power amplifiers are used to amplify amplif y the signal in various stages so that it helps in effective transmission of the signal. The combiner, combines the output of power amplifiers and feeds it to the antenna for transmission. The Figure 3.5 shows the block diagram of Harris 6kW transmitter. There are two exciters seen, in which one is a standby. s tandby. The Transmitter Control Unit (TCU) is t he controlling system of the transmitter. It monitors the working of the transmitter modules and it is also responsible for the protection of the modules. The TCU conta ins Master Controller Module (MCM) which controls all critical transmitter transmitt er functions. The Processor Control Module (PCM) in TCU is used for enhanced monitoring, fault log maintenance and web remote connectivity. The TCU also consists of a Graphical User Interface with a touch screen LED display. There are totally 12 power amplifier modules. Each module accounts for an amplification amplificat ion of 500W. Hence a total of 6kW power amplification is achieved with 12 amplifiers.
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Figure 3.5: Block Diagram of Harris 6kW DTT
The Power amplifiers are followed by a RF combiner circuit. The output of the combiner is given to a directional coupler. A channel filter is placed before the directional coupler in order to eliminate the noises present. The outer part of the directional coupler can be visualized as a 7-port patch panel where the signals of equally distributed powers are fed to upper and lower antenna present in the tower. Using the principles of Propagation of Electromagnetic waves the signals are radiated out at the frequency of 4898MHz.
3.5 EARTH STATION The earth station is an uplink center from which the signals are fed to the satellite for transmission in a specified area covered by the satellite. The signal is up-linked from earth station and received (or down-linked) by many down-link centers in TV broadcasting. The basic block diagram of the setup is shown in the Figure 3.6.
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UP-LINK
EARTH STATION
DOWN-LINK
DOWN-LINK CENTER
Figure 3.6: Basic Block Diagram of Earth Station
The earth station in DDK Bengaluru mainly consists of the following:
Playback Server Room
2+1 Chain Room
In Playback Server Room, the tape format programs are dumped into the server. This is called Ingestion. These files are usually stored with particulars e.g. name of the Program, type of tape, and details of tape with start and stop readings followed by day and date. In INGESTION system we recall these particular files and perform clean cutting operation by setting SET-IN and SET-OUT points and save this files to make them ON-AIR. Now, In PLAYBACK system, the clean cut saved files are ar e arranged orderly as per cue sheets given by Program Staff.
3.5.1 2+1 CHAIN ROOM The term “2+1” denotes that there are two are two chains denoted to two services servic es which are being uplinked and one chain which is a standby. The two services are
DD Chandana
Chandana Feed
If anyone of the above chains fail, the standby st andby chain will take over in place of the failed chain. The block diagram of 2+1 chain room is shown in Figure 3.7.
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DD Chandana and
Encoder 1
Chandana Feed
MUX-1
Junger Router
Modulator 1
Encoder 2
Watermark
MUX-1 Encoder 3
Modulator 2
Up SSPA-A
Converter 1
Combiner
3dB
Router
Splitter
(2x1)
Up SSPA-B
Converter 2
Up-Link Parabolic Dish
Figure 3.7: Block Diagram of 2+1 Room
The basic block diagram of the 2+1 Set-Up Room is shown in the Figure 3.7. The working of the 2+1 setup is as follows.
The SD-SDI output from the playback room is fed in to the 2+1 room.
The junger is used to modify the sound density and loudness level of the digital audio.
The feed line is used during live news program.
The SD-SDI input is 270mbps but the maximum allocated data transfer rate is 9.375mbps therefore compression is done in MPEG-2 format for audio and MPEG-4 for video in the Encoder. Thereby the output of encoder is 8.6mbps.
The output of encoder is fed to a multiplexer which give a Transport Stream as output.
For the purpose of transmission over long distances modulation is done for which modulator is employed.
The Modulation used here is QPSK. The baseband input signal is modulated over a carrier frequency of 70MHz to obtain a sinusoidal modulated wave.
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The output is fed to a router since only a single encoder and modulator is functioning in one cycle of operation. The router is basically a selective circuit.
The 3dB splitter is employed to split an RF input signal into many outputs. No losses occur in 3dB splitter. The output of the splitter is fed to an Up-Converter which combines input signal with a local oscillator signal to produce an RF signal of frequency 6.203MHz.
The RF signal requires sufficient power for Transmission. Hence SSPA’s are used which are built using MOSFET’s. MOSFET’s.
Since these signals are in Microwave range waveguides are used to transmit signal from SSPA to Parabolic Dish Antenna.
Table 3.1: Satellite Details of Earth Station Earth Station Parameters
Satellite
GSAT-17, 93.5˚ E GSAT-17,
Service
DD Chandana
Up-Link Frequency
6203.5MHz
Down-Link Frequency
3978.5MHz
Symbol Rate
6.25MSPS
FEC (Forward Error Correction)
3/4
Modulation
QPSK
Azimuthal Angle
128.25˚
Elevation Angle
66˚
Transponder
C.07
3.6 DIGITAL SATELLITE NEWS GATHERING (DSNG) DSNG system is used as a mobile Earth Station. To perform live broadcasting from a remote place where any physical link like optical fiber, transmission wire, radio link are not available, then satellite link is the only way to send the raw footage to the main TV station s ystem together with a mini program control system. The signal flow of the DSNG system is given in Figure 3.8.
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Figure 3.8: Typical DSNG Setup, (1+1 Configuration)
The digital audio and video are obtained as outputs from the OB Van. For live outdoor recordings OB (Outdoor Broadcasting) Van is used. The compression standard is MPEG-2. There are two types of DSNG systems which operates i n C-band and Ku- band. They are
Fly away type.
Van type.
DSNG setup comprises Encoder (MPEG2-MPEG4), Modulator (DVB-S/S2), Up-Converter, HPA (SSPA) and Parabolic Dish Antenna. Redundancies are provided at encoder, modulator, up-converter and HPA level with switching devices at each stage. The Figure 3.9 shows a DSNG Van with a Dish Antenna at the top. The parameters of DSNG are given in Table 3.2.
Figure 3.9: DSNG Van
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Table 3.2: DSNG Parameters
GSAT-16, for Ku band 55˚ 55 ˚E
Satellite
GSAT-17, for C band 93.5˚ 93.5 ˚E Up-Link Frequency Frequency
13774MHz
Down-Link Frequency
12527MHz
Symbol Rate
2.9 MSPS
FEC (Forward Error Correction)
3/4
Azimuthal Angle
240˚ 240˚
Elevation Angle
60˚ 60˚
Transponder
K.01
In case of failure of the DSNG then a backup system known as TVU pack is employed. A TVU pack is a small system which accepts video and audio signals from any source and compresses it and sends over a mobile network to be transmitted further to satellite. A block diagram of TVU Pack is shown in Figure 3.10. It has multiple dongles, which enables the use of multiple service providers for transmission. In case of failure of one service provider another service provider is chosen immediately.
BSNL/JIO/A IRTEL NETWORK
TVU PACK
CAR/MSR
EARTH STATION VIDEO
AUDIO
SATELLITE
Figure 3.10: TVU Pack Block Diagram
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4. WEEKLY REPORT
WEEK 1: STUDIO During the first week of the internship I learnt about the two studios at DDK. There are two studios in DDK. Studio-1 is used for programs which require big sets and variety of backgrounds. Programs such as “Shubhodaya Karnataka” Karnataka”, “Thatt Antha Heli” Heli ”, etc. are the few of which that are shot here. Studio-2 is used for live telecast of daily News. PCR, MSR, CAR and VTR are few sections involved in production of the programs. These are the places where the background processing takes place. I also learnt about audio control, vision mixing, and lighting control, different types of lights available and different types of microphones that are used while shooting the programs.
WEEK 2: EARTH STATION, TRANSMITTER AND DTH In the second week of the internship, I was involved in learning about Transmitter and Earth Station Complex. During this time, I learnt about Analog and Digital Terrest rial Transmission. I was able to identify the advantages of digital transmission over analog. I learnt about DVBT2 standard that is used in terrestrial transmission. In the earth station complex I learnt how the video and audio signals are modulated and upconverted to up-link the signals to satellite through antenna. I also leant about the satellites that DDK is currently using for telecasting. Then I lea rnt about Casper CG server, which is used to to queue the programs that need to be telecasted according to the list provided by the production department. I also learnt about different antennas involved in up-linking, down-linking and terrestrial transmission transmissi on of the signals. A briefing on DTH was also given in this week.
WEEK 3: ENG SECTION AND EDITING In the third week I learnt about the editing process. I was briefed about the software tools used in editing the videos. Editing is of two types i.e. Linear Editing and Non Linear Editing. Adobe Photoshop, Adobe CS, Canopus, Avid HD are some of the tools used for editing. e diting. In the ENG section I learnt about different cameras such as DVC Pro, XD Cam and NS Cam used in outdoor news gathering and also different microphones used for rec ording the sound. I also learnt about TVU Pack which is a standby for DSNG. Department of Telecommunication Telecommunicati on Engineering, B.I.T.
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WEEK 4: OB VAN, DSNG AND HANDS-ON SESSION ON AUDIO CONSOLE In the final week of my internship I learnt about OB Van and DSNG. OB Van is used for Outdoor Recording such as live events. The DSNG Van is a mobile earth station which is used to up-link the video and audio signals recorded by OB Van to the satellite for Live Telecast. In the second half of the week, I was given an opportunity to handle the audio console. I lear nt how to manage the amplitude of the voices collected colle cted using microphone. I learnt how to set-up se t-up microphones on a set. I also learnt how to separate the sounds on different instruments and isolate them so that its quality can be enhanced.
WEEKLY REPORT TABLE WEEK NO.
TOPIC
Week 1
STUDIO SECTION
Week 2
EARTH STATION,
SIGNATURE OF
SIGNATURE OF
EXTERNAL
INTERNAL
SUPERVISOR
SUPERVISOR
Mr Niranjan
Prof. Jamuna M.
Deputy Director (Engg.),
Assistant Professor
DDK, Bengaluru
BIT, Bengaluru
TRANSMITTER AND DTH Week 3
ENG SECTION AND EDITING
Week 4
OB VAN, DSNG AND HANDS-ON SESSION ON AUDIO CONSOLE
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5. CONCLUSION
In this report a detailed discussion discuss ion of Earth station complex and Transmitter at DDK Bengaluru has been made. Block diagrams of various transmitters are explained in this report. Interning at Doordarshan was a good opportunity for me to develop practical knowledge on the concepts that I had been learning throughout my course in a classroom. With this Internship I gained knowledge on how real time transmitters and receivers work. I also learnt about the steps involved in shooting a program to till it gets telecasted on a TV. The internship gave deeper insights on fundamentals of Television Broadcasting. This internship helped me to strengthen my knowledge base. It was a good experience overall.
Department of Telecommunication Telecommunicati on Engineering, B.I.T.
17
Earth Station Complex
2018-2019
REFERENCES
[1] Doordarshan Kendra Bengaluru Files Transmitter and Earth Complex. [2] Hand-outs on OB Coverage for TV Report at DDK Bengaluru. [3] http://www.ddchandana.gov.in/
Department of Telecommunication Telecommunicati on Engineering, B.I.T.
18
