Reminiscences on Radio Communication By DR T.H. CHOWDARY * Director, Center for Telecom Management &...
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Transcript of Reminiscences on Radio Communication By DR T.H. CHOWDARY * Director, Center for Telecom Management &...
Reminiscences on Radio Communication
By
DR T.H. CHOWDARY* Director, Center for Telecom Management & Studies
• Chairman, Pragna Bharati (Intellect India), Andhra Pradesh• Fellow: Tata Consultancy Service Ltd.
* Former Information Technology Adviser, Government of A.PChairman & Managing Director
Videsh Sanchar Nigam Ltd., Bombay
T: +91 (40) 6667-1191(O) 2784-3121®F: +91 (40) 6667-1111 (O)
Talk@ Broadcasting Engineering Society, Hyderabad15 Dec 2013
S705_Dec2013 2
Independent India’s First Minister For Broadcasting
• Today Dec 15 is the 63rd Vardhanti of Sardar Patel
• Independent India’s First Minister for Information & Broadcasting • It would be most appropriate to dedicate our Annual
Conventions to the Sardar’s Memory who unified and integrated Bharat as no emperor has ever done
• He was liberator of Hyderabad, integrator of India – a feat neither Ashoka nor Samudra Gupta nor Akbar nor the Queens & Kings of Great Briton (nor Bismark) could do.
S705_Dec2013 3
Strong Man…Veto
“The Sardar (Patel) was the strong man among the Indian leaders . Any discussion which failed to recognise the fact were likely to be unfruitful. He was essentially practical man with whom business could be done but if he was left out, he was in opposition to invoke a veto just as crippling as anything known to UNO
– G.S.Bozman British Secretary, Information & Broadcasting Ministry
(Source: Sardar Vallabhai Patel by B.Krishna; page 289)
S705_Dec2013 4
Patel: blunt to Mountbatten, G.G
“ We will deal with that question (Princes); leave it to us. You take no sides. Let paramountcy be dead – May 1947
“ You won’t govern yourself and you won’t let us govern”
- Sept 1947
S705_Dec2013 5
They said these are of no value (1)
I think there is a world market for, may be five computers”, said Thomas Watson, Chairman of IBM in 1943.
They said these are of no value (2)
“There is no reason anyone would want a computer in their home” said Ken Olson, Chairman & Founder of Digital Computer Corporation in 1971
6S705_Dec2013
They said these are of no value (3)
“The telephone has too many short comings to be seriously considered as a means of communication. The device is inherently of no value to us”. Read an internal Memo of the Western Union of the USA in 1876.
7S705_Dec2013
They said these are of no value (4)
• “The wireless music box ( Radio) has no imaginable commercial value. Who would pay for a message sent to nobody in particular (i.e radio broadcast-THC) said David Sarnoff (the future Chairman of the famed Radio Corporation of America (RCA) in response to a wireless company urging him for investment in Radio manufacturing in 1920.
8S705_Dec2013
They said these are of no value (5)
• The same misanthropic view was expressed in regard to wireless communication. An Editorial in the prestigious journal, “The Electrician” stated in the year 1903 that, “ wireless over very long distances appears to us impossible. That the ether waves inherently tend to follow the curvature of the earth as suggested by some writers is an absurdity .
9S705_Dec2013
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They said these are of no value (6)
This last one was in the context of various scientists offering their views for publication in Electrician, the most authoritative journal of the time.
They said these are of no value (7)
But all these very wise men proved to be absolutely fallible about which they expressed so much pessimism. All the devices attracted mass consumption
11S705_Dec2013
S705_Dec2013 12
Wireless Communications
• 1st demonstrated by Sir Jagdish Chandra Bose in Calcutta in 1895
• But patented by Guglielmo Marconi• Marconi Wireless telegraph Messages from
Cornwall in England to Newfoundland, Canada
S705_Dec2013 13
Wireless Propagation• Ionosphere – Oliver Heavyside A Telegraph operator in New Castle till 1874
Theoretical & mathematical work • Appleton - Discovery of a reflecting layer at a height of 90 Km
& Effect of earth’s magnetic field• Diurnal & seasonal variations• Sun-spot cycles – Magnetic storms• Short waves – Different Frequencies differently refracted• Aerials – Arrays – Beams• Radio Colony Delhi• Receiving Station in Todapur, Delhi• Monitoring : Simla
S705_Dec2013 14
f1
f2
f3
Ɵ1 Ɵ2 Middle East
Europe
c
Ɵ3
Journey thro’ Ionosphere or Heaviside/Appleton Layers
Limited Spectrum for Mobile Broadband
Best mobile broadband (300 MHz-3.5 GHz)
Bounces from the sky Bounces inside rooms
Penetrates buildings and terrain Reflects from buildings
Follows Earth’s curvature Travels in a straight line
Fades in the rain
1 MHz 10 MHz 100 MHz 1 GHz 10GHz75 meters 7.5 meters 0.75 meters 7.5 cm 75mm
15S705_Dec2013
Radio Spectrum- Bands & FrequencyBand Frequency in
GHZBand Frequency in
GHZL 1-2 U 40-60S 2-4 V 50-75C 4-8 E 60-90X 8-12 W 75-110
Ku 12-18 E 90-140Ka 26.5-40 D 110-170Q 30-50
Infra Red – Light - Ultra Violet Below 1 GHZ : LW, MW, SW, VHF, UHF, SHF
16S705_Dec2013
* Spectrum divided into Bands. Different bands allocated for different services –ITU *Assignments by National Licensors/ Regulators
Spectrum Requirements
2G 3G BWA
10MHZ 60MHZ 500MHZ
900 & 1800MHZ bands
2,100 MHZ band 2,300MHZ band
17S705_Dec2013
S705_Dec2013 18
Broadcasting
• Sound & Pictures – 1910s & 1920s• War of the worlds by H G Wells• Private in India from Mumbai• Government takes over• Relays- Transmission Media: Coaxial Terrestrial MW• USA Coast to Coast : 1915
S705_Dec2013 19
Communication Satellites
• Early Bird – 1965• Telstar: AT&T• geo=-synchronous orbit 36,500 Km above the equator• 100s of satellites – space debris• Worldwide coverage• DBS- TV & Radio
S705_Dec2013 20
Marconi’s Clout-Private State
• Marconi’s Wireless Telegraph Co (Later Cable & Wireless) out of BPO’s reach• Scientist/Engineers vain tirade against BPO’s monopoly • J A Fleming – 1901 Essay on detrimental effect of State Monopoly in electrical
communication Domestic B’casts- monopoly but VOA, BBC, Radio Moscow,
Radio Sri Lanka, PRCJammingRadio Liberty/ Free EuropeGorbachev’s Glassnost- Collapse of USSR
S705_Dec2013 21
Radio Frequency: Scarce Resource
• Myth of scarcity • Government’s greed & scams & misapplication
of spectrum revenues• Efficient use of spectrum- different
technologies• Intelligent Radio • Same all road width used by different brands of cars Why not all Telcos use all the full bandwidth?
S705_Dec2013 22
Liberalisation of Broadcasting• Private in 1920’s in Bombay• Acquisition by Government• Sardar Patel: Expansions-• NDA- Satellite channels for private cos• F.M spectrum auctions by I&B• 839 FM Channels in @ 400 KHZ spacing in 294 cities (>100K Pop)
Rs.1532 cr licence fee• Senseless: No news on F.M channels while allowed on TV channels• 24 hours –Trash idiotize viewers• Interent Radio & TV Stationary & Mobile• Devices – Transistor, Radios, TV Sets, PCs, Cell-phones, Smart-
phones
S705_Dec2013 23
Sensible use
• Restrict to (12 to 16) hrs/day• TV Channels & Radio (AIR & F.M) to be used
for election – No rallies & meetings• Internet voting• ICT-based marriages• Obligate to carry national programs on
literature, culture, music, dance, history, science, projects
S705_Dec2013 24
Dhanyawad:Thank You