DDK Delhi -Vocational training by Raisaket

Download DDK Delhi -Vocational training by Raisaket

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<p> Vocational Training Report HELD AT DOORDARSHAN KENDRA MANDI HOUSE, COPERNICUS MARG NEW DELHI, 110001 SUBMITTED BY S A K E T R A I ECE 4th Year, Roll No. 1003031097 INDERPRASTHA ENGINEERING COLLEGE, GZB, U.P.</p> <p>ACKNOWLEDGEMENT</p> <p>This report is an outcome of industrial training, which I have gone through at Doordarshan Kendra, Mandi House, Copernicus Marg, New Delhi, 110001; during the period 10th Jun to 9th Jul 2013.On the very outset of this report I would like to express my sincere &amp; heartfelt obligations to:DDG (E): Shri Shyam Narain Singh,DD (E): Shri Rakesh Kumar Chauhan,Assistant Er. : Shri R. N. Rai (Mentor),&amp;All engg. Supporting staff: Sh. Vinod Gupta, Sh. S. K. Dixit, Sh. S. P. S. Gulati, Sh. P. K. Mehrotra, Sh. P. Arun, Sh. Prashant Shingle, Sh. Govind Ballabh, &amp; Sh. T. C. Bagauli for creating tremendous atmosphere of excitng training programme at DDK. It was really a great experience working at DDK and learning from such experienced engineers with hands on the experience on the subject.I also would like to appreciate my colleagues Mr. Prashant Kr. Shukla, Mr. Pulkit Jain &amp; Mr. Rahul Aurora, who attended the entire training with me as per the scheduled by DDK.</p> <p> Saket Rai ECE 4th Year, 1003031097INDERPRASTHA ENGG. COLLEGE, GZB, U.P. </p> <p>INDEX</p> <p>Sr. No. Topic Page No. 1. About Doordarshan 01- 02 2. TV Studio 03-063. Production Control Room 07-094. Transmission Control Room 10-125. Master Switching Room 13-146. Earth Station 15-197. Satellite Communication 20-248. HPT Pitampura 25-289. OB Van 29-3210. DSNG 33-3511. DD Archives 36-3812. Essence 39-40 ABOUT ..DOORDARSHAN KENDRA DELHI is one of the oldest Kendra started on experimental basis on 5th September 1959 from a makeshift studio at Akashvani Bhawan,New Delhi as a part of All India Radio. Regular transmission was started from 1965. Govt. of India constituted Doordarshan in 1976, as a public TV broadcaster, as a separate department in broadcasting. Actually, Doordarshan developed itself during Asian Games 1982, held in Delhi. Continuous development in each &amp; every sections of Doordarshan has made it one of the largest broadcasting organization in the world in terms of infrastructure of studios &amp; transmitters.</p> <p>Presently Doordarshan operates with 35 channel classified as: Seven All India Channels- 1. DD National, 2. DD News, 3. DD Sports, 4. DD Bharati, 5. DD Rajya Sabha, 6. DD Gyandarshan, 7. DD Urdu; Eleven Regional Language Satellite Channels(RLSC), Fifteen State Network (SN) &amp; International Channels, One DD India Channel, One HDTV Channel;Doordarshan is also providing multi channel TV coverage in country through its free to air service; DD Direct Plus.DD is also running a mobile television service in Delhi.T V Studio</p> <p>Doordarshan shooting arena is termed as TV Studio. Basically, it is a production hall to shoot out various programs by just creating artificial sets as per requirements. </p> <p>Followings are the pre- requisites for a TV Studio:1. Lighting systems, winches &amp; control boards2. Cameras (3/4) with teleprompter3. Video &amp; Audio Monitors4. Make room with entire facilities5. Furnitures &amp; decoration items6. Cyclorama &amp;curtains7. Proper air conditioning systems8. Efficient sound absorbers9. Smooth &amp; plain surface to move cameras10. Effective communication with other sections11. Digital clock display system12. Warning light, alarm systems &amp; fire fighting equipments.</p> <p>Doordarshans main Recording TV Studio comprises 192 direct lights, 48 dimmers, 3 /4 digital cameras &amp; 3 /4 artificial shooting sets etc.</p> <p>T V Studio lighting technique:T V Studio lighting technique depends upon following four parameters -1. Quantity of Iight: Means amount of radiated energy by the source of light.2. Quality of light: Means the type of light source is used.3. Contrast ratio: Difference between highly lighted &amp; darkest part of the scene.4. Color temperature:Different light colors have their own temperatures e.g.- Fire- 1930K, Domestic lamp- 2780K, Studio lamp- 3200K, HMI-5600K, Sun light- 5600K, Fluorescent- 6500K, Cloudy day- 6500K, Clear blue sky-12000K.In T V Studio standard three point lighting technique is used, as shown below:1. Key light: used to highlight an object from the front. (Hard light cum 100% balance of light)2. Fill light: used to suppress the shadow created by key light. (Soft light cum 85% balance of light) 3. Back light: used to separate the object from back ground, so to produce 3-D visualization. (Hard light cum 110% balance of light) Production Control Room Production Control Room (PCR) is also known as Studio Control Room (SCR) or Gallery. Signals generated in TV Studio are controlled using certain effects &amp; characters are generated here.Facilities in a PCR include: Avideo monitorwall, with monitors for program, preview,VTRs, cameras, graphics and other video sources. In some facilities, the monitor wall is a series of racks containing physical television and computer monitors; in others, the monitor wall has been replaced with a virtual monitor wall (sometimes called a "glass cockpit"), one or more large video screens, each capable of displaying multiple sources in a simulation of a monitor wall.</p> <p> Avision mixer, a large control panel used to select themultiple-camera setupand other various sources to be recorded or seen on air and, in many cases, in anyvideo monitorson the set. The term "vision mixer" is primarily used in Europe, while the term "video switcher" is usually used in North America.</p> <p> Aprofessional audiomixing consoleand other audio equipment such as effects devices.</p> <p> Acharacter generator(CG), which creates the majority of the names and fulldigital on-screen graphicsthat are inserted into the programlower thirdportion of thetelevision screen Digital video effects, or DVE, for manipulation of video sources. In newer vision mixers, the DVE is integrated into the vision mixer; older models without built-in DVE's can often control external DVE devices, or an external DVE can be manually run by an operator. A still store, or still frame, device for storage of graphics or other images. While the name suggests that the device is only capable of storing still images, newer still stores can store moving videoandmotion graphics. Thetechnical director's station, withwaveform monitors,vector scopesand thecamera control units(CCU) or remote control panels for the CCUs. In some facilities, VTRs may also be located in the PCR, but are also often found in thecentral apparatus room IntercomandIFBequipment for communication with talent andtelevision crew Asignal generatortogenlockall of the video equipment to a common reference that requirescolor burst</p> <p>TRANSMISSION CONTROL ROOM</p> <p> Transmission Control Room (TCR), also termed as Tx Room or Presentation Suites is a room at broadcast facilities &amp; TV Stationsaround the world.TCR is staffed 24x7 by on-air presentation coordinators who are responsible for the continuity and punctual play out of scheduled broadcast programming.Programming may be live from the TV Studio or played from video tapes or from video server play out. When broadcast programming is live the presentation coordinator will override the broadcast automation system &amp; manually switch the TV Programming. Live Programming is unpredictable and will affect the scheduled timing of scheduled programming events; the presentation coordinator adjusts programming to bring the schedule back on time by adding or removing fill content from the play out schedule.Common TCR equipmentsBroadcast Automation Server (for large playlist items almost up to 500 items),Video Tape Recorder (VTR),Computer Graphics (CG),Non-linear Editing device,Production Switcher,Broadcast quality Video Monitor,Waveform Monitor,SDI Audio de-embedder.</p> <p>There are total 72 electronic equipments of aforementioned type in the Transmission Control Room of DD National. Basically, the automation of various PCR equipments is done in order to achieve seamless transmission. It is also required to minimize the time elapse as well as manual errors occurred during transmission.Each &amp; every equipment has its own defined port on Production Switcher. Applying automation one can switch the particular device at particular time.Finally, these equipments are connected to a Navigation PC through a Hub Switch for error diagnosis purpose.TCR is smaller in size as compare to the Master Switching Room. This is a scaled down version of centralcasting.</p> <p> MASTER SWITHING ROOM </p> <p>Master switching room (MSR) is also known as Heart of the Studio and used for transmission media.</p> <p> It is the engineering co-ordination center of activity for selecting &amp; routing the signal from various sources to transmitter and earthstation.</p> <p> It is a room where all different sources from the outside studio comes first here and enroots transmission to different destination like transmitter &amp; earth station. </p> <p>This room comprises of:</p> <p> Routine Switcher, Stab amplifier, Video / Audio distribution amplifier, Color Stabilization amplifier, Sync generator, Frame synchronizer, Digital clock monitoring system, Logo generator, Vectro- scope, Waveform monitor, Video monitor, Hum Suppressor, Video Equalizer, Change over unit. </p> <p> The CONTROL CONSOL PANEL consisting the control of Routine Switcher, Stab amplifier, Frame synchronizer &amp; other MSR Equipments are stored here.</p> <p>EARTH STATIONEARTH STATION is most significant part of Doordarshan from communication point of view, as shown in figure:</p> <p>Transmitting E/S Receiving E/S UPLINK DOWNLINK </p> <p>Digital Earth Station operates in frequency range 5.85 GHz to 6.425 GHz for transmission and 3.625 GHz to 4.24 GHz for reception of the signal. </p> <p>Description of General Configuration of an Earth Station:</p> <p> Digital information in the form of binary digits when enters earth station and is then processed (filtered, multiplexed, formatted etc.) by the base band equipment.</p> <p> The encoder performs error correction coding to reduce the error rate, by introducing extra digits into digital stream generated by the base band equipment. </p> <p> The function of the modulator is to accept the symbol stream from the encoder and use it to modulate an intermediate frequency (I.F) carrier. In satellite communication, I.F carrier frequency is chosen at 70 MHz for communication using a 36 MHz transponder bandwidth.</p> <p> The modulated I.F carrier is fed to the up-converter and frequency-translated to the uplink R.F frequency of C-Band or Ku-Band as per desire. This modulated R.F carrier is then amplified by the high power amplifier (HPA) to a suitable level for transmission and radiation by the parabolic dish antenna to the satellite. e.g.: Klystron amplifier, TWTA &amp; SSPA.</p> <p> On the receive side, the earth station antenna receives the low-level modulated R.F carrier in the downlink frequency spectrum.</p> <p> The low noise amplifier (LNA)/ low noise block convertor (LNBC) is used to amplify the weak received signals and improve the signal to Noise ratio (SNR). The error rate requirements can be met more easily. R.F is to be reconverted to I.F at 70 MHz because it is easier design a demodulation to work at such frequencies than in any of the GHz range.</p> <p> The demodulator estimate which of the possible symbols was transmitted based on observation of the received I.F carrier.</p> <p> The decoder performs a function opposite that of the encoder. Because the sequence of symbols recovered by the demodulator may contain errors, the decoder must use the uniqueness of the redundant digits introduced by the encoder to correct the errors and recover information-bearing digits.</p> <p> The information stream is fed to the base-band equipment for processing for delivery to the terrestrial network.</p> <p> The downlink Beacon frequency is the concept, so that tracking equipments track the satellite and align the beam towards it to facilitate communication.Fig. General configuration of an Earth Station</p> <p> SATELLITECOMMUNICATION</p> <p>Satellite Communication plays a vital role in the global telecommunication systems. This technology was started in abroad in 1960, and in India this was adopted in 1975.Near about 2000 artificial satellites are orbiting Earth relay analog &amp; digital signals carrying voice, video and data to &amp; from one or many locations worldwide.Satellite communication uses geostationary satellite and operates in C &amp; Ku band mostly.First Indian National Satellite (INSAT) was launched in 1982.</p> <p>Satellite Orbits: Types</p> <p>Geostationary satellite:</p> <p>A circular orbit 35,785 km (22,236 miles) above Earths Equator in which a satellite orbitalperiod is equal to Earths rotation period of 23 hours and 56 minutes. A space craft in this orbit appears to an observer on Earth to be stationary in the sky. This particular orbit is used formeteorological and communications satellites.</p> <p>The geostationary orbit is a special case of geosynchro- nous orbit, which is any orbit with a period equal toEarths rotation.Satellite Transmission Frequency Bands:</p> <p>Satellite in Use:Orbit type: Geo-synchronousOrbital location: 93.5 E</p> <p>Presently Doordarshan is using a latest, powerful &amp; largest geosynchronous satellite of INSAT series with high power Ku- Band transponders to uplink the DD dire...</p>

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