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8/18/2019 Repoert Pta

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CHAPTER 1

INTRODUCTION

1.1 AN OVERVIEW

All India Radio (AIR),officially known since 1956 as Akashvani (voice of the sky ) ,is

the national public radio broadcaster of india and a division of rasar !harati" #stablished

in 19$%, it is the sister service of rasar bharati&s 'oordarshan, the national public television

broadcaster"

he word Akashvani * was coined by +"" -opalaswa.y after settin/ up the

nation&s first private radio station in his residence, ittal ihar* in 19$6"Akashvani .eanscelestial announce.ent*0 the world of anskrit ori/in , is often found in hindu .ytholo/y"

All India Radio is one of the lar/est radio networks in the world" Its head2uarters is at the

Akashvani bhavan in 3ew 'elhi" Akashvani !havan houses the dra.a section, the 4+

section and the 3ational ervice "'oordarshan endra ('elhi) offices are also located on

the sith floor at Akashavni !havan"

1.2 PRESENT STATUS

Akashvani Alwar is the ro/ra. roduction 7enter in the Alwar 'istrict" he studies are

housed at +an/al ihar,alwar and the trans.itter is located at the centre" As per the census

fi/ures of 8%%1,8: by area of Alwar"" here are ;6"5%: 34 $$" $% .ins

weekly) in ?indi > Ra@asthan" ro/ra.s are also telecast in indhi, =rdu, and #n/lish >

anskrit at this kendra"

1.3. BRIEF HISTORY

he first license /ranted for trans.ittin/ a broadcast was /iven on 4ebruary 8$,

1988" he Radio 7lub of 7alcutta was the first radio club to start functionin/ in

3ov198;

he introduction of the co..ercial channel Bividh!harti& in Cctober 195

increased the interest and popularity of radio"


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AIR today has a network of 8$8 broadcastin/ centres with 1;9 .ediu.

fre2uency(+D), 5; hi/h fre2uency (D) and 11 4+ trans.itters"he covera/e is

91"9: of the area servin/ 99"1;: of the people

AIR covers 8; Ean/ua/es and 1;6 dialects in ho.e services

1.4. GENERAL INFORMATION ABOUT AIR

• I3'=RF G All India Radio

• 4C=3'#' G 8$ Huly 198

• +AI3 ?#A'=AR#R G 3ew 'elhi,India

• AR#A #R#' G India

• 7?AIR+A3 G +rs" +rinal andey

• CD3#R G -overn.ent of India

• #+ECF## G 1"$ .illion(8%18)

• #RI7# G !road castin/, 3ews and #ntertain.ent

• D#!I# G www"prasarbharti"co.

• R#CRI3- C44I7#R G +r" "" -upta

•

RAI3I3- '=RAIC3 G $% days

1.5. ALL INDIA RADIO WINGS

1.5.1 ENGINEERING WING

In respect of technical .atters the 'irector -eneral is assisted by the #n/ineerin7hief and

Additional 'irectors -eneral(#) in the head2uarters and the Jones" In addition there is a

lannin/ and 'evelop.ent =nit in the ?ead2uarters in respect of 'evelop.ent lan

che.es of All India Radio" 4or 7ivil 7onstruction activities, the 'irector -eneral is

assisted by the 7ivil 7onstruction Din/(77D), which is headed by a 7hief #n/ineer" 77D

also caters to the needs of 'oordarshan"

1.5.2 ADMINISTRATIVE WING

http://www.prasarbharti.com/http://www.prasarbharti.com/


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Additional 'irector -eneral (Ad.inistration) and a 'eputy 'irector

-eneral(Ad.inistration > 4inance) assists the 'irector -eneral on .atters of

ad.inistration and finance, while Additional 'irectors -eneral (ro/ra.) assists '- in

ad.inistration of ro/ra. personnel" A 'irector looks after the #n/ineerin/ Ad.inistration

of All India Radio"

1.5.3 SECURITY WING

he security set up co.prises of a 'eputy 'irector -eneral (ecurity), Assistant 'irector

-eneral (ecurity) and a 'eputy 'irector (ecurity)" hey handle .atters of the security

and safety of AIR installations, trans.itters, studios, offices etc" he ecurity needs of

'oordarshan are also looked after by these officers"

1.5.4 AUDIENCE RESEARCH WING

he 'irector Audience Research heads the =nit of Audience Research in the 'irectorate"

urveys to /au/e listenin/ habits and pro/ra. preferences for effective pro/ra. plannin/ at

various stations of All India Radio are handled by field units under the supervision of the

'irectorate"

he birth of broadcastin/ in India has started on an eperi.ental basis in the year

1981,when ti.es of India in collaboration with > depart.ent broadcast a .usical pro/ra." In the year 19$% radio broadcastin/ started operatin/ under the Indian

broadcastin/ co.pany" he /overn.ent took over the char/e of broadcastin/ in +arch

19$5" A separate office of the controller of broadcastin/ was created" he land.ark in the

history of broadcastin/ is the chan/e of the na.e of the Indian broadcastin/ to air in 19$6

and in the sa.e year 'elhi station was for.ed" 4ro. 19$6 onwards the develop.ent of air

was very slow0 nine stations were opened up in different places like 'elhi, 7alcutta,

!o.bay, +adras, Eucknow and iruchi" 4ro. 1956 onwards air was popularly known as

AA?DA3I" Cn 18th 3ove.ber 19; the voice of -andhi @i was broadcasted in air and

since then it is celebrated as broadcastin/ day" AIR and AAA?DA3I ai.s to provide

infor.ation, education and entertain.ent for the public" elevision (Akashvani) started in

India in the year 1959 with black and white trans.ission" he black > white trans.ission

was converted fully into color in 19


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(a) Ea!" S!a!#$% (&) G'a T$*

fg1:-Earth Station

7hannels ? E E ransponder otal

''1 11< ;$ 855 1< 11$;

'' 3ews 69 9 5 % 15$

Cthers ; ; % % % ;

Re/ional 6 9 9; % 1%9

Table1.1:- Channels Transmitter


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CHAPTER 2

ORGANISATIONAL INFRASTRUCTURE

2.1 ALL INDIA RADIO

2.1.1 INTRODUCTION

Cn the first decade of broadcastin/, it epanded enor.ously but pro/ra.s was watched

/enerally in black > white set up to .odern strea.in/ online" rans.ission in India

started in a te.porary studio with the eperi.ental telecast in @aipur on the 19th of au/est

1965" Radio service ca.e to +u.bai (also known as !o.bay) and A.ritsar in the early

period of the %s" =ntil 195, only a couple of Indian cities can access television service

and paid surveys Akashvani, which was a /overn.ent owned RA'IC co.pany, re.ained

the only provider of radio in India

In as early as 1991, AIR Alwar has been usin/ a 1% kw power trans.itter" he reach of the

3ews channel is at $8: nationwide audience share" AIR Alwar trans.itter is at ch" 3o"5,

+an/al ihar and the studios are found at +an/al ihar, Alwar" he channel covers al.ost


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5" 'i/ital earth link station rans.itter

#ach of these depart.ents are discussed in detail with due stress to the relevant en/ineerin/

aspects" he studio has 7a.era and li/hts and other e2uip.ent re2uired for production of a

feed"

All India Radio (AIR),one of the lar/est radio networks in the world is a division of rasar

!harati (!roadcastin/ 7ooperation of India) currently workin/ under the 7hair.anship of

.t" MRINAL PANDEY and S"# +AWAHAR SIRCAR as its 7hief #ecutive Cfficer

#stablished in 19$6, today it is the sister service of rasar !harati&s 'oordarshan, the national

television broadcaster"

All India Radio is also known as Akashvani" he head 2uarter is at the Akashvani !havan,

3ew 'elhi"

AIR today has a network of 8$ broadcastin/ centers with 1;9 .ediu. fre2uency (+D), 5;

hi/h fre2uency (D) and 1 4+ trans.itters" he covera/e is 91"


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2.1.3 PRASAR BHARATI

rasar !harati has .ainly two branchesG

Fig.2.2:- "rasar #harati

2.1.4 INFRASTRUCTURE

All India Radio ca.e to be known as Akashvani fro. 195" 4ro. a .ea/er 1< rans.itters in 19;

AIR ac2uired ;6 by the end of 1st plan, 59 by 8nd plan, and 11% by the end of


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8" 7onsultancy services includin/ feasibility studies, turnkey @obs and operations > .aintenance in the

specialiLed fields of

(i) errestrial !roadcastin/ for Radio and elevision" his includes the fre2uency plannin/, covera/e

plannin/, syste. desi/n, and installation, testin/ and co..issionin/ operation"

(ii) atellite !roadcastin/G his includes plannin/ and syste. desi/n, eecution and operation of fied

and .obile (3-) uplink and downlink syste.s usin/ both analo/ and di/ital technolo/ies"

(iii) tudio syste.s includin/ interior desi/n, acoustics, stateoftheart Radio > studios" "

(iv) 'ata !roadcastin/ > Internet !roadcastin/" "

(v) Acoustics and audio video syste. for theatres, auditoriu.s and conference halls"

$" urnkey solutions for establish.ent of 5% Datt 4+ 7o..unity Radio tation for

=niversitiesK7olle/esKResidential chools"

;" ellin/ of Air ti.e on +DK4+KD !roadcast trans.itter network of AIR to educationalK

a/ricultural institutes"

5" rovidin/ on site and institutional trainin/ in various disciplines of broadcastin/"

• ro@ect I.ple.entation and coordination"

• oftware develop.ent, 3onlinear #ditin/ and Ani.ation"

• Cperation and +aintenance of broadcast rans.itter and tudio #2uip.ent"

• 3etwork lannin/ and +ana/e.ent"

6" oftware develop.ent and content packa/in/"

" 7ivil > #lectrical construction work specially for broadcastin/ setups, Auditoriu.s and conference

halls etc"


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• 'i/ital 3ews /atherin/ for Radio 3K 7ellularK A honeK I'3"

• Radio 3ews roo. Auto.ation syste.

• R' > 'AR7 on 4+ trans.itters

9" erfor.ance +easure.ent and 4ield tren/th urvey Analysis of !roadcast yste. after

co.pletin/ ro@ect"

1%" est facilities for Acoustic .aterial testin/ "Acoustical .easure.ents and #lectro Acoustic

ransducer"

2.1., POLICIES

• o initiate appropriate .easures > develop business opportunities to undertake profitable

pro@ects and activities in broadcastin/ sector"

• o allow other broadcasters K teleco. providers to use rasar !harati hardware K software

infrastructure by char/in/ license fee K usa/e fee"

• o provide consultancy > services to various broadcastin/ or/aniLations, private co.panies,

teleco. service providers, Is etc"

• o undertake syste. desi/n, inte/ration with eistin/ infrastructure, drawin/ of specifications,

costin/, for.ulation of proposals > other related works for the clients"

• o undertake installation, operation and .aintenance of broadcastin/ facilities"

• o harness inner stren/ths of the or/aniLation to identify, develop and consolidate its resource

base"

• o /enerate revenue by takin/ profitable venture in the field of broadcastin/, co.puters and

co..unications"

• o provide world class consultancy services and undertake turnkey @obs in the specialised field

of broadcast en/ineerin/ and related areas"

• o facilitate /rowth of Indian !roadcastin/ > eleco..unication sector by opti.al utiliLation

of !roadcastin/ facilities and resources"

• o beco.e pre.ier national and /lobal provider of broadcast trans.ission infrastructure and

related services"


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2.1.- THREETIER BROADCASTING SYSTEM

AIR has a threetier syste. of broadcastin/" hese three levels of pro/ra.s are the 3ational, Re/ional

and Eocal each havin/ distinct audiences"

Fig2.$:- T%REE-TIER #ROADCASTIN! S&STE'

3ational pro/ra.s are broadcast fro. 'elhi for relay by the 7apital, Re/ional and Eocal Radio tations"

o.e of these are the 3ational ro/ra. of alks and 4eatures in ?indi and #n/lish, the 3ational

ro/ra.s of .usic"

THREE TIER

BROADCASTING

LOCALREGIONALNATIONAL


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"

• he Na!#$%a/ 7hannel of All India Radio located in 'elhi broadcasts pro/ra.s which are

heard on +ediu. Dave and also on hort Dave" tarted on 1 4a.ily

Delfare and pro/ra.s for Do.an, 7hildren etc"

• L$a/ Radio is relatively a newer concept of broadcastin/ in India" Eocal radio stations

serve s.all co..unities, showcase local culture and broadcast area specific pro/ra.s for

the benefit of the co..unity" he trans.ission is in the 4+ .ode" he pro/ra..in/ is

fleible and spontaneous and the stations function as the .outh piece of the local

co..unity" At present there are


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2.2 SHARP ELECTRONICS

2.2.1 INTRODUCTION

At harp India, our challen/e is to create a balance between work ti.e and personal ti.e,

with products that can benefit peopleMs lives at work, at ho.e, and everywhere in between"

harp consu.er electronics can enhance your [email protected], add to your co.fort and open

new perspectives" harp business products can boost your productivity and reduce costs"

harp products are desi/ned to help individuals, fa.ilies, and corporate tea.s connect

effortlessly, co..unicate clearly, and unleash creativity like never before" harp is

dedicated to i.provin/ peopleMs lives throu/h the use of advanced technolo/y and a

co..it.ent to innovation, 2uality, value, and desi/n"

2.2.2. BACGROUND

harp considers India to be an etre.ely i.portant .arket for its products" It is a .easure

of this stron/ belief in the Indian .arket , that it has three subsidiaries in India"

• harp India Ei.ited which set up operations in 19 yste.s > Cffice Auto.ation

products like 'i/ital +ultifunction roducts, 4acsi.ile +achines, +ulti.edia

ro@ectors ,rofessional E7' 'isplay outions, ideo Dall 'isplay olutions,

#lectronic 7ash Re/isters > C er.inals etc

2.2.3 ORGANISATIONAL STRUCTURE

CHAIRMAN

+r" unil u.ar inha

Ma%a0#%0 D#*!$

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+r" o.io Iso/ai

NON E*'!#* I%*6*%*%! D#*!$

+r" an@ay aidya

2.2.4BUSINESS SERVICES

harp #lectronics ervices co.bine capabilities acrossG

• .ana/e.ent

• consultin/

• technolo/y

• business process outsourcin/

to provide fleible and scalable endtoend services" !usiness ervices address the

.ost pressin/ needs of clients by industry and by enterprise function"

I%'7!8 B'7#%*77 S*#*7 address the business and perfor.ance issues that are

uni2ue to a /iven industry"

F'%!#$% B'7#%*77 S*#*7 address issues and processes in specific enterprise

functions, such as procure.ent or hu.an resources, which are applicable across

industries" Accenture !usiness ervices span all four of our /rowth platfor.sN

trate/y

'i/ital

echnolo/y

Cperation

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2.2.5 SHARP PRODUCTS

• 9%* $' Internet E#'

• A2uos uattron $' Internet E#'

• Refri/erators

• +icrowave Cvens

• Air 7onditioners

• acuu. 7leaner

• Dashin/ +achine

• ?ealsio

2..2., WORFORCES

he four workforces serve clients in the areas of consultin/, technolo/y, and outsourcin/, as

well as the co.pany itself" his is al.ost always an internal desi/nation as it is co..on

place for harp #lectronics e.ployees to work in blended tea.s for a variety of reasons"

• 7onsultin/G 4ocus on .ana/e.ent consultin/, process desi/n work and the

application of technolo/ies to business" Responsible for sales, delivery, and

leadership of .ost of harpMs pro@ectbased work"

• ervicesG +ost focus on outsourcin/ en/a/e.ents in the areas of business

operations, I, applications develop.ent and .aintenance, help desk services, and

?R" As part of so.e outsourcin/ deals, clientsM internal tea.s can be Orebad/edO as

harp e.ployees ali/ned to this workforce" o.eti.es they work on 7onsultin/

pro@ects or as internal #nterprise tea.s"

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• he harp #lectronics echnolo/y olutions subsidiary focuses on the specific

technolo/y skills needed to deliver pro@ects or outsourcin/ arran/e.ents" 7o.prises

the .a@ority of harpMs e.ployees in delivery centers in developin/ countries like

,India""

• #nterpriseG 4ocus on .ana/in/ and supportin/ all the activities across harpMs

business, includin/ le/al, security, facilities, .arketin/, and client financial

.ana/e.ent"

2.2.- OPERATING GROUPS

As .ost consultin/ fir.s, harp #lectronics operates in a .atri structure" he first ais is

dedicated to the operatin/ /roups, or industries of its clients" !roadly, the five Cperatin/

-roups areG

• 7o..unications, +edia > echnolo/y

• 4inancial ervices

• roducts

• Resources

• ?ealth > ublic ervices

he five Cperatin/ -roups co.prises 19 industry sub/roups that focus on industry

evolution, business issues, and applicable technolo/ies"

2.2. GROWTH PLATFORMS

he second ais is the /rowth platfor.s, which broadly refers to the functional or technical

do.ains in which harp #lectronics creates and delivers solutions to clients"

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• harp #lectronics was launched .iraculous las.a cluster Ion echnolo/y in Hune

8%1; to provide services for clients related to business strate/y, technolo/y strate/y

and operations strate/y"

• +iraculous las.a cluster Ion echnolo/y provides clients with di/ital .arketin/,

analytics and .obility services"

• echnolo/y unifies the full ran/e of #lectronics syste.s inte/ration, technolo/y

consultin/, and I outsourcin/ capabilities" +ost people in the ervices and

olutions work forces are ali/ned under the echnolo/y /rowth platfor."

• harp #lectronics operations focuses on .ana/in/ specific business processes or functions for clients such as procure.ent, ?R, finance and accountin/, as well as

services /eared to the needs of specific industries"

2.2.9 CAREERS AT SHARP ELECTRONICS

It has been brou/ht to the notice of harp !usiness yste.s (India) Ei.ited +ana/e.entthat, so.eone is sendin/ fake e.ails C3 !#?AE4 C4 O?AR -RC=O infor.in/ the

candidates to apply for O'irect Recruit.ent CfferO, for various locations in India by payin/

the security deposit in cash in a fictitious !ank Account 3o "

harp !usiness yste.s (India) Ei.ited hereby clarifies that we have neither authoriLed nor

appointed any person for sendin/ such recruit.ent offers throu/h e.ails nor have anycorporate office in 3oida and plants at 'elhi and !an/alore as stated in the fake e.ail"

All are re2uested to take note of the sa.e > do not respond to any such fake e.ails fro.

any unauthoriLed person on behalf of harp !usiness yste.s (India) Ei.ited"

harp !usiness yste.s (India) Ei.ited will not be responsible, if any person acts in

response to such fake e.ails and to the conse2uences arisin/ thereof"

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Fig 2.( Shar) Ele*troni*s ogo

.

CHAPTER 3

TECHNOLOGY

3.1 SATELLITE COMMUNICATION

3.1.1 I%!$'!#$%

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atellite 7o..unication is the outco.e of the desire of .an to achieve the concept of

/lobal villa/e" enetration of fre2uencies beyond $% +e/a ?ertL throu/h ionosphere force

people to think that if an ob@ect (Reflector) could be placed in the space above ionosphere

then it could be possible to use co.plete spectru. for co..unication purpose"

3.1.2 H#7!$8

In an article published in Direless Dorld* in 19;5 Arthur 7" 7larke foresaw that it would

be possible to provide co.plete covera/e of world fro. @ust three satellites, provided that

they could be placed at -eostationary orbit* i"e", at an orbit $5,99 + above the e2uator"

4or placin/ the satellite at this hei/ht, the speed of satellite should be $"%; k.Ksec" Cr

11,8%% k.Khour" his was indeed the pioneerin/ concept on satellite co..unication even

thou/h the article was .eant to be scientific fiction" ?owever, the re2uired technolo/y to

put satellite in space was not available at that ti.e and so the scientists and en/ineers did

not take this article by 7larke seriously"

=R could .aster rocket technolo/y and put putnik P I* the world&s first satellite in

space in 195 fro. !aikonourcos.odro..e in aLakhstan" his was the be/innin/ of

satellite era" putnikI was a low orbit satellite and wei/hed 11%% lbs" his was indeed

re.arkable achieve.ent by any standard especially liftin/ a pay load of 11%% lbs in the

.aiden atte.pt itself" putnikI could broadcast radio si/nals to earth on $1"5 +?L" It

orbited 16 revolutions per day and its life was 9% days" In 196% =A launched #choI and

#choII fro. 7ape 7anaveral" hese were passive satellites and could only reflect the si/nal

.echanically and could not receive, a.plify or chan/e the fre2uency before re

trans.ission" In 1968 the world&s first active satellite elstar was launched fro. 7ape

7anaveral by =A which .ade history in relayin/ Eive !roadcast* to #urope on 1% Huly,

1968" elstar was also low orbit satellite but active satellite" In 196;, ynco. the world&s

first /eosynchronous satellite was launched by =A fro. 7ape 7anaveral" ynco. had

relayed the okyo Cly.pic live elevision covera/e to =A for the first ti.e in the world"

Around the sa.e ti.e, +olniya satellite was launched by =R but it was a low orbit

active satellite with an inclination of 66o" his orbit was found the best suited to cover the

northern part of =R effectively and so this is preferred by the Russians even now"

IntelsatI (nick na.ed as #arly !ird) was launched on 8 April 1965" his was parked in

/eosynchronous orbit in Atlantic Ccean and provided teleco..unication or television

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service between =A and #urope" It had capacity for 8;% one way telephone channels or

one television channel" ubse2uently IntelsatII /eneration satellites were launched and

parked in Atlantic ocean and acific Ccean" 'urin/ Intelsat III /eneration, not only Atlantic

and acific ocean /ot satellites but also Indian Ccean /ot satellite for the first ti.e" 3ow

Arthur 7" 7larke&s vision of providin/ /lobal co..unication usin/ three atellites with

about 18% de/rees apart beca.e a reality" o far Intelsat has launched /enerations of

/eosynchronous satellites in all the three re/ions na.ely Atlantic Ccean, acific Ccean and

Indian Ccean"

4or national as well as nei/hborin/ countries covera/e, so.e of the followin/ satellites are

usedG

A3I G 7anadian satellite syste.

I3A G Indian atellites

A=A G Australian atellites

!RAJIEA G !raLilian atellites

4R#37? #E#7C+G 4rench atellites

IAEA G Italian atellites

7?I3AA G 7hinese atellites

AIC3A,-CRIJC3G Russian atellites"

here are also satellites operated by private or/aniLations and so.e of these are /iven

below G

-AEAQF G Cwned by ?u/hes 7orporation

A7C+ G Cwned by R7A

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! G atellite !usiness yste.s

A G Cwned by A3A+A

AIAA G Cwned by 7hina Bsatellites tate 7o..unication for

echnolo/y and industry

pace prophet Arthur 7" 7larke was the first person to predict the .odern day satellite

co..unication" In his scientific fiction in Direless Dorld* in 19;5 he foresaw that it

would be possible to provide co.plete radio covera/e usin/ three satellites placed in

-eosynchronous orbit* at an hei/ht of $5,9 + above earth or ;8,15 + fro. the

centre of earth" It was a re.arkable prediction at that ti.e when it was felt it would be

shear wasta/e ti.e to think of placin/ satellite in space" ?e calculated that if a satellite had

to re.ain in space at an hei/ht of $5,9 + it should revolve with a velocity of $"%;

+Ksecond so as to ac2uire centrifu/al force to neutralise the force of attraction of earth"

Dith this velocity, the satellite will .ake one revolution in 8$ hours 56 +inutes and ;

seconds and this is the actual period of rotation of earth on its own ais" his is known as

sidereal day (reference of rotation for sidereal day is a distant star and for solar day,reference of rotation is sun)" olar day has 8; hours as the reference for rotation is sun"

he earth is not re.ainin/ in the sa.e location every day but is revolvin/ around the sun

and thus advancin/ about one de/ree per day" In a year, it would have advanced $65

de/rees (about one full day) in a year and this would have produced one additional rotation

of earth on its own ais" hus there are $66"85 sidereal days in a year as co.pared to

$65"85 solar days" his correspondin/ly reduces the sidereal day ti.e fro. 8; hours (solar

day) to 8$ hours, 56 .inutes and ;"1 seconds" ince earth is actually .akin/ one rotation

on its own ais in 8$ hours, 56 +inute and ;"1 seconds the /eosynchronous satellite should

also .ake one revolution durin/ this period as to re.ain at sa.e point while lookin/ fro.

earth"

wo technolo/ies responsible for the birth of atellite 7o..unication yste. are G

1" Rocket echnolo/y"

8" +icrowave echnolo/y

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he econd Dorld Dar favoured the epansion of these two technolo/ies" atellite is

basically a reflector in the sky"

3.2 Aa%!a0*7 $: 7a!*//#!* C$;;'%#a!#$%

he followin/ are the advanta/es of satellite co..unication

his is only .eans which can provide .ulti access two way co..unication" Dithin the

covera/e area, it is possible to establish one way or two way co..unication between any

two points"

he cost of trans.ittin/ infor.ation throu/h satellite is independent of distance involved"atellite can be used for two way co..unication or broadcast purpose with the covered

area"

atellites are capable of handlin/ very hi/h bandwidth" 3or.ally any satellite can

acco..odate about 5%% +?L in 7 !and" 4or ea.ple the bandwidth of I3AI is ;


22/49

Fig $.1 Satellite Comm+ni*ation Ar*hite*t+re

atellite 7o..unication yste. co.prises of two ele.ents G

a" -round e/.ent

b" pace e/.ent

3.3.1 T"* S6a* S*0;*%!

he space se/.ent contains the atellite and all terrestrial facilities for the control and

.onitorin/ of the atellite" his includes the trackin/, tele.etry and co..and stations

(>7) to/ether with the atellite control centre where all the operations associated with

stationkeepin/ and checkin/ the vital functions of the satellite are perfor.ed" In our case it

is +aster 7ontrol 4acility (+74) at ?assan"

he radio waves trans.itted by the earth stations are received by the satellite 0 this is called

the up link" he satellite in turn trans.its to the receivin/ earth stations 0 this is the down

link" he 2uality of a radio link is specified by its carriertonoise ratio" he i.portant

factor is the 2uality of the total link, fro. station to station, and this is deter.ined by the

2uality of the up link and that of the down link" he 2uality of the total link deter.ines the

2uality of the si/nals delivered to the end user in accordance with the type of .odulation

and codin/ used"

22


23/49

3.3.2 T"* G$'% S*0;*%!

he /round se/.ent consists of all the earth stations 0 these are .ost often connected to the

enduser&s e2uip.ent by a terrestrial network or, in the case of s.all stations (ery .all

Aperture er.inal, A), directly connected to the enduser&s e2uip.ent" tations aredistin/uished by their siLe which varies accordin/ to the volu.e of traffic to be carried on

the space link and the type of traffic (telephone, television or data)" he lar/est are

e2uipped with antenna of $% . dia.eter (tandard A of the I3#EA network)" he

s.allest have %"6 . antenna (direct television receivin/ stations)" 4ied, transportable and

.obile stations can also be distin/uished" o.e stations are both trans.itters and receivers"

Cthers are only receivers 0 this is the case, for ea.ple with receivin/ stations for a satellite

broadcast syste. or a distribution syste. for television or data si/nals"

3.4 SPACE GEOMETRY

3.4.1 T86*7 $: O!

he orbit is the tra@ectory followed by the satellite in e2uilibriu. between two opposin/

forces" hese are the force of attraction, due to the earth&s /ravitation, directed towards the

centre of the earth and the centrifu/al force associated with the curvature of the satellite&stra@ectory" he tra@ectory is within a plane and shaped as an ellipse with a .ai.u.

etension at the apo/ee and a .ini.u. at the peri/ee" he satellite .oves .ore slowly in

its tra@ectory as the distance fro. the earth increases"

3.4.1.1 E//#6!#a/ $!7


24/49

satellite carries in low altitude circular orbits are for e"/" IRI'I=+, -EC!AE AR,

C'F#F, ARI#, E#CA, AR3#, etc"

3.4.1.3 C#'/a $!7 with Lero inclination (#2uatorial orbits)" he .ost popular is

the /eo stationary satellite orbits 0 the satellite orbits around the earth at an altitude of

$5


25/49

Fig .$.2 Satellite Earth Station ,)lin Do/nlin Chain

3.5.1 Ta%7;#77#$% $: &a7* &a% !$ Sa!*//#!*

he base band si/nal consists of video (5 +?L), two audio subcarriers (5"5 +?L > 5"5

+?L) and ener/y dispersal si/nal (85 ?L)" After .odulation (% +?L) and upconversion

(6 -?L) the carrier is a.plified and uplinked throu/h olid arabolic 'ish Antenna ('A)"

'own link si/nal can be received throu/h sa.e 'A usin/ ransReceive 4ilter (R4) and

Eow 3oise A.plifier (E3A)" After down conversion to % +?L, it is de.odulated to /et

audio and video"

Sa!*//#!* Ta%76$%*

As shown in fi/";, the uplinked si/nal (6 -?L) at satellite is received, a.plified and down

converted to ; -?L band and sent back throu/h filter and power a.plifier (D)" he

local oscillator fre2uency of down converter is 8885 +?L for 7 band and #7 band

transponders"

Fig.$.$ #lo* 0iagram o Satellite Trans)on0er

25


26/49

R**##%0 Sa!*//#!* S#0%a/

4or receivin/ a satellite si/nal we need followin/ e2uip.ent G

1 atellite receivin/ antenna ('A)"

8 4eed with low noise block converter (E3!7)"

$ Indoor unit consistin/ of satellite syste. unit and a ynthesised satellite receiver"

S8%!"*7#7*TVRO S87!*;

A si.plified block dia/ra. of ynthesiLed RC yste. is /iven in 4i/""arabolic 'ish

Antenna ('A) is widely used to receive the satellite si/nals" -ain of a 'A is directly

proportional to the s2uare of fre2uency bein/ received and its siLe" After reflection fro.

'A, si/nal stren/th is .ai.u. at the focus of 'A, so feed is placed at its focus with the

help of a .ountin/ plate" 4or the reception of band si/nal we use helical feed while for

7band si/nal we use feedhorn" 4or a.plification and down conversion of the received

si/nal the E3!7 is connected at the output of the feed" E3!7 down converts the si/nal in

the ran/e of 115% +?L to 95% +?L for !and, 1;5% +?L to 95% +?L for 7band and

185% +?L to 95% +?L for # 7band" EC 4re2uency of !and E3!7 is $65% +?L and

that of 7band and #7 band is 515% +?L and 55% +?L respectively" 88 '7 supply

is fed to E3!7 throu/h R4 cable fro. satellite syste. unit"

he downconverted si/nal fro. E3!7 is fed to satellite syste. unit where it /ets divided

into two parts to .ake input R4 si/nal for satellite receivers"

F#0'* $: M*#! (G=T*>)

'own link 7arrier to noise density of a satellite down link si/nal is /iven as G

( ) klossPathT

GEIRPN

C

eqsat

Do−−+=

where k is !oltL.ann&s constant (88


27/49

his is an i.portant para.eter of earth station which decides the 2uality of a RC

yste."

Fig.$.( Snthesi3e0 T4RO Sstem

ECIL S8%!"*7#?* TVRO

A typical #7IE synthesiLed RC is shown in fi/"


28/49

Fig.$.5 T.4. Re*ei6e Terminal

3.5.2 I%$$ U%#!7

he indoor unit contains two units" hey are G

1" yste. unit

8" atellite Receiver =nit

3.5.3 S87!*; '%#!

he syste. unit contains a passive power divider and power supply for the E3!7" he

power divider divides the I4 into two e2ual parts to be applied to the two receivers" he

power supply is fed throu/h sa.e cable to the E3!7"

3.5.4 Sa!*//#!* R**#* U%#!

he satellite receiver contains the down converter, videoKaudio de.odulators and

processin/ circuits" 4inally we /et two videoKaudio outputs"

28


29/49

A synthesiLed receiver accepts si/nal in the ran/e of 9%% to 1%% +?L" he block dia/ra.

of a typical #7 receiver is shown in fi/ure 9"

he I4 is applied to a foursta/e low noise a.plifier for a.plification" he overall /ain of

the a.plifier is around 88 d!" his si/nal is then applied to 4# .ier where a EC

fre2uency of 15%% to 8$%% +?L is .ied so that an I4 of 6%% +?L is produced"

he local oscillator consists of two si.ilar 7Cs (volta/e controlled oscillator) one

operatin/ in the ran/e of 15%% 1;9 +?L and the other in the ran/e of 15% to 8$%% +?L"

hey are controlled by a synthesiLer I7" A sa.ple of the EC fre2uency is taken and phase

co.pared with a stable reference crystal fre2uency of ; +?L and error if any, is then

applied to the 7C for fre2uency correction throu/h a low pass filter" hus the 7C works

in a phase locked loop .ode"

3., RADIO NETWORING TERMINAL

3.,.1 I%!$'!#$%

he various All India Radio stations spread throu/hout the nation are re2uired to relay

certain pro/ra.s which are ori/inatin/ fro. 'elhi" i.ilarly there are certain pro/ra.s

which are ori/inatin/ fro. capital stations are relayed by the other stations in that re/ion"

In order to link 'elhi and capital stations with other AIR stations, R3 throu/h I3A is not

only cost effective but also provide the /ood technical 2uality as co.pared to 'C lines

and D linka/e"

he Radio 3etworkin/ ter.inal located at AIR stations receive !and or 7 !and

trans.issions" he pro/ra.s thus received after processin/ are fed to the trans.itter for

broadcast purposes" hus R3 acts as the /round ter.inal for satellite si/nal reception"he block dia/ra. of band R3 ter.inal is shown in fi/ure 1%"

29


30/49

Fig. $.7 #lo* Diagram o S-#an0 RN Re*ei6e Terminal 8RNT9

he R3 syste. consists of the followin/ units G

# O'!$$ U%#!

• 18 ft" 7hicken .esh parabolic antenna and feed unit"

• Eow noise A.plifier (E3A)• 4ront #nd 7onverter (4#7)"

## I%$$ U%#!

30


31/49

• assive ranslator =nit (4)"

• Active ranslator =nit (4A)"

• ynthesiLed ranslator"

• Audio 'e.odulator

• ower upply"

3.,.1.1 O'!$$ U%#!

Paa&$/# D#7" A%!*%%a< T"* 18 ft" parabolic dish antenna collects the R3 carriers

trans.itted by the satellite and feeds the. to the feed .ounted E3A unit" he pri.e focus

reflector is used for R3" he /ain of this antenna is $6"5 d!i" A helical feed of 8"5 turns

capable of /ivin/ circularly polariLed wave is used" 7ircular polariLation of I3A

broadcast is used as it does not re2uire any [email protected] of feed or polariLation .atchin/"

S&a% L$ N$#7* A;6/#:#* (LNA)


32/49

3.- LATITUDE AND LONGITUDE

Any place of the earth if it has to be located or .arked should have so.e coordinates which

anybody can follow" As such there are no fied references ecept north and south poles"

?ence so.e i.a/inary lines were drawn, called lon/itudes and latitudes" Dith these lines it

is very easy to fi coordinates of any place with reasonable accuracy"

3.-.1 LATITUDE

4or a start a line was drawn e2uidistant to both north and south poles and this was called

e2uator" arallel lines were drawn depictin/ the an/ular distance north or south of e2uator"

All latitudes are circles with different dia.eters the e2uator bein/ the lar/est" As they are

parallel to each other they are also called parallels" he e2uator as the reference and both

north and south poles cover an an/le of 9% de/rees .ai.u." (4i/" 9 > 1%)"

Fig. $. "arallels o atit+0es Fig. $.; atit+0e as

ang+lar 0istan*e

32


33/49

3.-.2 L$%0#!'*

he latitude /ives only one reference point and we need another one" 4or this purpose so.e

other lines were drawn touchin/ both the poles as shown in fi/"

9 > 1%"

he reference point i"e" % de/ree lon/itude is supposed to pass throu/h the observatory at

-reenwich, #3-EA3'" he .eridians or lon/itudes east of -reenwich are called east

.eridians and those lyin/ in the west are called west .eridians" he .ai.u. is 1


34/49

!oth the aLi.uth and elevation of a dish can be affected by three factors for /eostationary

satellites" hey are

1" he lon/itude of the satellite"

8" he latitude of the place"

$" he lon/itude of the place"

Ca/'/a!#$% $: A%0/* $: E/*a!#$%

( )

φ−

−φ= −

2

1

Cos.DCos1

R

r Cos.DCos

tanElevation

where r S Radius of the earth (6$6 k.s)

R S Radius of ynchronous orbit (;8,165 k.s)"

φ S Eatitude of the earth station

' S difference in lon/itude of the earth station and the satellite" (λr λs)

Ca/'/a!#$% $: A?#;'!"

( )( )φ

±= −sin

Dtantan180azimuth

1o

where ' S λr λs in de/rees"

φ S latitude of the /iven site in de/rees"

34


35/49

λr S lon/itude of the /iven site in de/rees"

λs S lon/itude of the satellite"

P$/a#?a!#$%

he wave radiated by an antenna consists of an electric field co.ponent and a .a/netic

field co.ponent" hese two co.ponents are ortho/onal and perpendicular to the direction

of propa/ation of the wave" !y convention the polariLation is defined by the plane of

propa/ation of electrical field co.ponent" hat .eans if the electrical field co.ponent is

travellin/ in the vertical plane it is called vertically polariLed" If the wave contains both

vertical and horiLontal co.ponents it is called circular or elliptical" he types of

polariLationG

1 Einear polariLation

a) ertical ()

b ) ?oriLontal (?)

8 7ircular or #lliptical

a Ri/ht hand circular (R?7)

b) Eeft half circular (E?7)"

3. AMPLIFIERS

An electronic a.plifier is a device for increasin/ the power a.plitude of a si/nal" It does

this by takin/ ener/y fro. a power supply and controllin/ the output to .atch the input

si/nal shape but with lar/er a.plitude" In this sense, an a.plifier .ay be considered as

.odulatin/ the output of the power supply"

3..1 T86*7 $: a;6/#:#*7

A.plifiers can be specified accordin/ to their input and output properties" hey have so.e

kind of /ain, or .ultiplication factor relatin/ the .a/nitude of the output si/nal to the input

35


36/49

si/nal" he /ain .ay be specified as Ooutput volta/eKinput volta/eO, Ooutput powerKinput

powerO or any other co.bination of current, volta/e and power" In .any cases, with input

and output in the sa.e units, /ain will be unit less0 for others this is not necessarily so P for

ea.ple, a trans conductance a.plifier has a /ain with units of conductance (output current

per input volta/e)"

In .ost cases an a.plifier should be linear, that is the /ain should be constant for any

co.bination of input and output si/nal" If the /ain is not linear, e"/" by clippin/ the output

si/nal at the li.its of its capabilities, the output si/nal is distorted"

3..2 C/a77#:#a!#$% $: a;6/#:#* 7!a0*7 a% 787!*;7

here are .any alternative classifications that address different aspects of a.plifier desi/ns,

and they all epress so.e particular perspective relatin/ the desi/n para.eters to the

ob@ectives of the circuit" A.plifier desi/n is always a co.pro.ise of nu.erous factors,

such as cost, power consu.ption, realworld device i.perfections, and a .ultitude of

perfor.ance specifications" !elow are several different approaches to classificationG

Input Cutput 'ependent source A.plifier type

I I current controlled current source 777 current a.plifier

I current controlled volta/e source 77 trans resistance a.plifier

I volta/e controlled current source 77 trans conductance a.plifier

volta/e controlled volta/e source 7 volta/e a.plifier

In practice the ideal i.pedances are only approi.ated" 4or any particular circuit, a s.all

si/nal analysis often is used to find the i.pedance actually achieved" A s.allsi/nal A7 test

current I is applied to the input or output node, all eternal sources are set to Lero, and the

correspondin/ alternatin/ volta/e across the test current source deter.ines the

i.pedance seen at that node as R S K I"

36


37/49

A.plifiers desi/ned to attach to a trans.ission line at input andKor output, especially R4

a.plifiers, do not fit into this classification approach" Rather than dealin/ with volta/e or

current individually, they ideally couple with an input andKor output i.pedance .atched to

the trans.ission line i.pedance, that is, .atch ratios of volta/e to current" +any real R4

a.plifiers co.e close to this ideal" Althou/h, for a /iven appropriate source and load

i.pedance, R4 a.plifiers can be characteriLed as a.plifyin/ volta/e or current, they

funda.entally are a.plifyin/ power"

C$;;$% !*;#%a/

Cne set of classifications for a.plifiers is based on which device ter.inal is co..on to

both the input and the output circuit" In the case of bipolar @unction transistors, the three

classes are co..on e.itter, co..on base, and co..on collector" 4or fieldeffect

transistors, the correspondin/ confi/urations are co..on source, co..on /ate, and

co..on drain0 for triode vacuu. devices, co..on cathode, co..on /rid, and co..on

plate"

U%#/a!*a/ $ /a!*a/

Dhen an a.plifier has an output that ehibits no feedback to its input side, it is called

unilateral" Cne conse2uence is the a.plifier has input i.pedance that is independent of the

load attached to the a.plifier, and output i.pedance that is independent of the si/nal source

drivin/ the a.plifier"

he opposite case is the bilateral a.plifier, where feedback connects the output to the input

side of the a.plifier" uch feedback often is deliberate, for ea.ple ne/ative feedback often

is used to tailor a.plifier behavior" ?owever, at least as often, feedback is both undesirable

and unavoidable0 introduced, for ea.ple, by parasitic ele.ents like inherent, undesirable

capacitances in transistors that couple input to output" In any case, a bilateral a.plifier has

an input i.pedance that depends upon the load attached to the a.plifier, and an output

i.pedance that depends on the source drivin/ the a.plifier"

Einear unilateral and bilateral a.plifiers can be represented by twoport networks" +ost

a.plifiers are bilateral to so.e de/ree, however they .ay often be .odeled as unilateral

under certain operatin/ conditions to si.plify the analysis"

I%*!#%0 $ %$%#%*!#%0

37


38/49

Another way to classify a.ps is the phase relationship of the input si/nal to the output

si/nal" An invertin/ a.plifier produces an output 1


39/49

for drivin/ speakers, so.eti.es with .ultiple a.ps /rouped to/ether as separate or

brid/eable channels to acco..odate different audio reproduction re2uire.ents"

T A special type of a.plifier is widely used in instru.ents and for si/nal processin/,

a.on/ .any other varied uses" hese are known as operational a.plifiers, (or opa.ps)"

his is because this type of a.plifier is used in circuits that perfor. .athe.atical

al/orith.ic functions, or OoperationsO on input si/nals to obtain specific types of output

si/nals" A typical opa.p has differential inputs (one Oinvertin/O, one, Ononinvertin/O

relative to the output) and one output" An idealiLed opa.p has the followin/

characteristicsG

o Infinite input i.pedance (so as to not load circuitry it is sa.plin/ as a control input)

o Jero output i.pedance

o Infinite /ain

o Jero propa/ation delay

he perfor.ance of an opa.p with these characteristics would be entirely defined by the

(usually passive) co.ponents for.in/ a ne/ative feedback loop around it, that is, the

a.plifier itself has no effect on the output"

oday, opa.ps are usually provided as inte/rated circuits, rather than constructed fro.

discrete co.ponents" All realworld opa.ps fall short of the idealised specification above P

but so.e .odern co.ponents have re.arkable perfor.ance and co.e close in so.e

respects"

I%!* 7!a0* $'6/#%0 ;*!"$

A.plifiers are so.eti.es classified by the couplin/ .ethod of the si/nal at the input,

output, or between sta/es" 'ifferent types of these includeG

Resistivecapacitive (R7) coupled a.plifier, usin/ a network of resistors and capacitors

!y desi/n these a.plifiers cannot a.plify '7 si/nals as the capacitors block the '7

co.ponent of the input si/nal" R7coupled a.plifiers were used very often in circuits with

vacuu. tubes or discrete transistors" In the days of the inte/rated circuit a few .ore

transistors on a chip are .uch cheaper and s.aller than a capacitor"

39


40/49

Inductivecapacitive (E7) coupled a.plifier, usin/ a network of inductors and capacitors

his kind of a.plifier is .ost often used in selective radiofre2uency circuits"

ransfor.er coupled a.plifier, usin/ a transfor.er to .atch i.pedances or to decouple

parts of the circuits

uite often E7coupled and transfor.ercoupled a.plifiers cannot be distin/uished as a

transfor.er is so.e kind of inductor"

'irect coupled a.plifier, usin/ no i.pedance and bias .atchin/ co.ponents

his class of a.plifier was very unco..on in the vacuu. tube days when the anode

(output) volta/e was at /reater than several 1%% and the /rid (input) volta/e at a few volts

.inus" o they were only used if the /ain was specified down to '7 (e"/", in an

oscilloscope)" In the contet of .odern electronics developers are encoura/ed to use direcly

coupled a.plifiers whenever possible"

F*>'*%8 a%0*

'ependin/ on the fre2uency ran/e and other properties a.plifiers are desi/ned accordin/ to

different principles"

T 4re2uency ran/es down to '7 are only used when this property is needed" '7

a.plification leads to specific co.plications that are avoided if possible"

T 'ependin/ on the fre2uency ran/e specified different desi/n principles .ust be

used" =p to the +?L ran/e only OdiscreteO properties need be considered0 e"/", a ter.inal

has input i.pedance"

T As soon as any connection within the circuit /ets lon/er than perhaps 1: of the

wavelen/th of the hi/hest specified fre2uency (e"/", at 1%% +?L the wavelen/th is $ ., so

the critical connection len/th is appro" $ c.) desi/n properties radically chan/e" 4or

ea.ple, a specified len/th and width of a 7! trace can be used as a selective or

i.pedance.atchin/ entity"

T Above a few 1%% +?L, it /ets difficult to use discrete ele.ents, especially

inductors" In .ost cases 7! traces of very closely defined shapes are used instead"

40


41/49

3.9 MODULATION

+odulation is a process of superi.posin/ infor.ation on a carrier by varyin/ one of its

para.eters (a.plitude, fre2uency or phase)"

3.9.1 N** :$ M$'/a!#$%

T +odulatin/ the si/nal over hi/her fre2uency can reduce antenna siLe"

T o differentiate a.on/ trans.issions (stations)

T +ai.u. to .ini.u. fre2uency ratio can be reduced to .ini.u. by .odulatin/ the

si/nal on a hi/h fre2uency"

3.9.2 T86*7 $: M$'/a!#$%

• A.plitude +odulation

• An/le +odulation

• ulse +odulation

3.9.2.1 A;6/#!'* M$'/a!#$%

If the a.plitude of the carrier is varied in accordance with the a.plitude of the .odulatin/

si/nal (infor.ation), it is called a.plitude .odulation" his .odulation has been shown in

fi/

41


42/49

Fig$.11 Am)lit+0e 'o0+lation

Bandwidth

!D S (fc f.) (fc f.) S 8f.

3.9.2.2 A%0/* M$'/a!#$%

ariation of the an/le of carrier si/nal with ti.e results in an/le .odulation" It is of two

types

a) 4re2uency +odulation

b) hase +odulation

a) F*>'*%8 M$'/a!#$%

If the fre2uency of the carrier is varied in accordance with the a.plitude of the

.odulatin/ si/nal (infor.ation), it is called fre2uency .odulation" his has been

shown in fi/ure

42


43/49

Fig $.12 Fre>+en* 'o0+lation

&) P"a7* M$'/a!#$%If the hase of the carrier is varied in accordance with the a.plitude of the

.odulatin/ si/nal (infor.ation), it is called phase .odulation"

Fig $.1$ "hase 'o0+lation

3.1@ RSNR21@ VHF FM S$/#S!a!* Ta%7;#!!*7

[email protected] F*a!'*7 $: Ta%7;#!!*


44/49

6" ound broadcastin/ at its very best 8"5 to $% kD"

[email protected] E#!*

• he lowpower R4 sta/es of a radio trans.itter ,

• It is used for .odulation purpose in trans.itter .

[email protected] Ra C$%!$//*

Rack controller is a line of controllers desi/ned for the .ore co.ple and advanced

syste.s" he availability of inputs and outputs covers the re2uire.ents of the .ost

sophisticated co.pressor racks in ter.s of the nu.ber and the function of the re2uired

control al/orith.s" he control software in si lan/ua/es, co.patible with the differentsiLes of hardware, satisfies both the .ost co..on control re2uire.ents as well as the .ore

advanced applications" ossibility to separate co.pressor and fan control on one sin/le user

interface, with local network connection between the controllers"

"

Fig $.1( Ra* Controller

[email protected] N*! C.C.U.

he 7ontrol =nit R> 3et77=UU3?K3U3R


45/49

Fig $.15 Net C.C.,.

[email protected] P$* A;6/#:#*

he ter. power a.plifier is a relative ter. with respect to the a.ount of power delivered to

the load andKor provided by the power supply circuit" In /eneral the power a.plifier is the

last Ma.plifierM or actual circuit in a si/nal chain (the output sta/e) and is the a.plifier sta/e

that re2uires attention to power efficiency" #fficiency considerations lead to the various

classes of power a.plifier based on the biasin/ of the output transistors or tubesG see power

a.plifier classes"

45

http://en.wikipedia.org/wiki/Electrical_loadhttp://en.wikipedia.org/wiki/Electrical_loadhttp://en.wikipedia.org/wiki/Biasinghttp://en.wikipedia.org/wiki/Biasinghttp://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classeshttp://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classeshttp://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classeshttp://en.wikipedia.org/wiki/Electrical_loadhttp://en.wikipedia.org/wiki/Biasinghttp://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classeshttp://en.wikipedia.org/wiki/Electronic_amplifier#Power_amplifier_classes


46/49

Fig $.17 Transmitter 81=$.1 '%39

3.11 ISOLATION TRANSFORMER

An isolation transfor.er is a transfor.er used to transfer electrical power fro. a source

of alternatin/ current (A7) power to so.e e2uip.ent or device while isolatin/ the powered

device fro. the power source, usually for safety reasons" Isolation transfor.ers

provide /alvanic isolation and are used to protect a/ainst electric shock, to suppresselectrical noise in sensitive devices, or to transfer power between two circuits which .ust

not be connected" A transfor.er sold for isolation is often built with special insulation

between pri.ary and secondary, and is specified to withstand a hi/h volta/e between

windin/s"

46

http://en.wikipedia.org/wiki/Transformerhttp://en.wikipedia.org/wiki/Electrical_powerhttp://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Galvanic_isolationhttp://en.wikipedia.org/wiki/Transformerhttp://en.wikipedia.org/wiki/Electrical_powerhttp://en.wikipedia.org/wiki/Alternating_currenthttp://en.wikipedia.org/wiki/Galvanic_isolation


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Fig$.1 Isolation tranormer

CHAPTER4

CONCLUSION

47


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he practical work done in colle/e durin/!"#" is not sufficient and therefore it is re2uired to

/o .ore about it > so it is necessary to take trainin/ in All India Radio "he ai. of such a

trainin/ is to learn the various aspect of the theoretical studies in practical field" It helped

.e to /ain knowled/e in practical aspect of en/ineerin/ studies" In All India Radio I saw

processin/ of various instru.ent practically which are use in study" etup of studio where

shootin/ perfor.ed li/htin/ ,different features of ca.era and all fil. .akin/ process

,recordin/ is done by video tape recordin/ "De know about the different type of

trans.ission of audio and video si/nal"

'ifference of trans.ission in live telecast and record telecast outdoor broadcastin/ van used

for live telecast" Idea about production control roo., vision .ier and .aster switchin/

roo." roper steps of trans.ission how can reach si/nal at our television si/nal" 'i/ital

earth station which is the .ost i.portant part of All India Radio and satellite

co..unication how can both are interact and downlink and uplink fre2uency and

advanta/e of satellite co..unication over terrestrial co..unication and nowled/e about

band and satellite orbit is the i.portant points which we are study in our co.plete tannin/

session"

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REFERENCES

1" www"air"co"in

8" httpGKKprasarbharati"/ov"inKAIRKInfor.ationKa/esKdefault"asp

$" AEE I3'IA RA'IC study .aterial

;" "'"rsad Antenna > Dave ropa/ation*

5" httpGKKen"wikipedia"or/KwikiKrans.itter

6" httpGKKen"wikipedia"or/KwikiK7o..unicationsVsatellite

" httpGKKallindiaradio"/ov"inKdefault"asp

repoert pta

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