The Thaicom Satellite System

Thaicom 1 & 2
In 1991, the government of the Kingdom of Thailand granted Shinawatra Computer and Communications Co. Ltd a 30-year concession to operate communications satellites for the country. Shortly thereafter, Shinawatra signed a US$ 100 million contract with Hughes Space and Communications Company governing the kingdom's first spacecraft, ground equipment and training of Shinawatra employees as satellite controllers. The system was named "Thaicom" by His Majesty King Bhumiphol to symbolise the link between Thailand and modern communications technology.

The first Thaicom satellite was launched on December 17, 1993. A second Hughes built spacecraft, Thaicom 2, was launched in October of 1994. Both spacecraft are based on the Hughes HS 376 spin stabilised satellite bus. Each of the first generation Thaicom satellites carry ten active C-band transponders linked to eleven-watt solid state power amplifiers. The C-ban beam coverage is fairly broad, covering a region that extends from Japan to Singapore. Each satellite also is equipped with two active Ku-band transponders powered by 47-watt travelling wave tube amplifiers which achieve an EIRP of 50 dBW over Thailand.

The Thaicom HS-376L satellites share some characteristics with the other HS 376 satellite models used by other organisations and companies around the world. The outer and inner cylindrical solar panels slide together for launch, and in orbit, the outer panel is lowered and the round, dual polarised antenna is raised. Silicon solar cells provide electrical power (700 watts at beginning of life for Thaicom 1 and 2) and a nickel hydrogen battery provides power during eclipses. Because of the light electronics payload aboard Thaicom 1 and 2, the satellites were able to carry several years' worth of additional fuel so that they can achieve a mission lifetime of 13.5 years in contrast to 8 to 10 years for other HS 376 models carrying more transponders.

Launch dates:	Thaicom 1: December 17, 1993 Thaicom 2: October, 1994
Current orbital locations:	Thaicom 1: 120 East Thaicom 2: 78.5 East
Mission Lifetime:	13.5 years
Contractors:	Hughes Space & Communications (prime) Telespace Ltd. (technical support)
Platform:	Lightweight version of Hughes HS-376 spin stabilised
Dimensions:	2.16 meters in diameter, 6.6 m in height with solar array drum extended
C-band Transponders:	Ten plus two transponders backup; 11-watt solid state power amplifiers
C-band Transponder bandwidth:	36 MHz
Ku-band Transponders:	Two plus one transponder backup: 47-watt travelling wave tube amplifiers
Ku-band Transponder bandwidth:	54 MHz

Thaicom 2 Satellite Coverage Maps
Each satellite is equipped with a single antenna comprising two offset grid reflectors with horizontal/vertical feed system on despun communications platform.

Thaicom 3 & 4

On April 16, 1997, Arianespace launched Thaicom 3, the third in a series of dual-band communications satellites serving the kingdom of Thailand. The launch of Thaicom 3 was a watershed event for operator Shinawatra Satellite Public Co. Ltd. The new spacecraft is allowing the company to provide international communications services across a vast region stretching from central Europe and Africa to eastern Asia and Australia. Built by Aerospatiale, Thaicom 3 is a Spacebus 3000A three axis stabilised satellite equipped with twenty-five C-band transponders, seven of which will transmit in a semi global beam that spans virtually all the inhabited land masses visible from the satellite's orbital assignment at 78.5 degrees east longitude. The remaining eighteen C-band transponders connect to a regional Asian beam that encompasses India, southern China, and Southeast Asia. Thaicom 3's fourteen Ku-band transponders are divided between a high-powered Thailand beam and a steerable beam that is currently focused onto India. On May 26, 1997, Thaicom 3 was collocated with Thaicom 1 & 2 at 78.5 degrees east longitude. All traffic previously carried by Thaicom 1 was transferred over to Thaicom 3 and Thaicom 1 was relocated to 120 degrees east longitude.

The collocation of satellites is one effective strategy which Shinawatra is using to get around the increased difficulty faced by Asian satellite operators in obtaining new orbital positions and co-ordinating their use with competing satellite systems within the region. Thaicom 3's high-power global beam transponders operate in the extended C-band frequency range of 3.4 to 3.7 GHz, thus expanding the number of active C-band transponders available at 78.5 degrees east longitude from twenty to thirty five. On Ku-band, Thaicom 3 represents a dramatic increase in capacity from just two active transponders on either of the first two Thaicom satellites to fourteen transponders, including as many as seven of which can been connected to a steerable Ku-band spot beam.

The relocation of Thaicom 1 to its new orbital assignment at 120 degrees east longitude represents another important strategy. Capacity on the relocated satellite, which consists of ten active C-band transponders in an east Asian beam and two active Ku-band transponders in a Thailand beam, has become available for lease to both domestic and regional satellite users. What's more, Aerospatiale is building a fourth dual-band Thaicom satellite which will be launched and collocated with Thaicom 1 at 120 degrees east longitude in the year 2000.

Contractors:	Aerospatiale (prime); Space Systems/Loral (repeaters)
Platform:	Spacebus 3000A three axis stabilised
Launch Mass:	2,650 kg
Span:	26 meters
Power supply:	5,300 watts
C-band Payload:	7 high power transponders over semi-global coverage (EIRP: 35 dBW) 18 medium power transponders for coverage over India and Indochina (EIRP: 37.3 dBW) 42-watt amplifiers
Ku-band Payload:	7 to 11 high power transponders over Thailand coverage (EIRP: 55 dBW) 3 to 7 high power transponders over a steerable beam (50.7 dBW) 97 and 102 watt amplifiers
Orbital location:	78.5 degrees East Longitude
Mission Lifetime:	14 years

Thaicom 3 Customers
The list of principal domestic users of the Thaicom system includes the kingdom's six licensed TV networks (Channels 3, 5, 7, 9, 11 and ITV), all domestic VSAT operators, and various Thai government agencies, including the Communications Authority of Thailand (CAT), the Telephone Organisation of Thailand (TOT) and the Thai military. Moreover, Thai cable TV operators IBC and UTV are using digital MPEG technology to distribute their programs from Bangkok to provincial wireless cable franchises and, in the case of IBC, to offer DTH reception at individual homes.

One of the major promises of the Thaicom system was the delivery of educational TV to rural students scattered throughout the Thailand's seventy-three provinces. Shinawatra, in fact, helped to set up the Thaicom Foundation, a non-profit educational organisation that was endowed with free capacity on the Thaicom satellite system.

One major aspect of the plan for Thaicom 3 was the inclusion of a steerable Ku-band spot beam for DTH program distribution. As one of the pioneers in digital DTH signal delivery, Shinawatra wanted the ability to export both its satellite technology as well as the company's hard won knowledge in the field. The ripest market during the satellite design period was India. Thaicom 3 carries a total of seven Ku-band transponders operating in the 12.25 to 12.75 GHz frequency range which can be connected to the steerable beam over India. Two of these transponders are fixed to the India beam, while five others can be switched between the India (nominal EIRP: 50.1 dBW) and Thailand (nominal EIRP: 55 dBW) beams.

Inside India, the national government recently issued a decree that Ku-band DTH dishes will have to be licensed by the Indian government. This temporary stop gap measure was introduced to give the country some breathing room to implement a DTH policy to protect its indigenous broadcast TV industry from the foreign invasion. The government's stance has set off a recent spate of demonstrations in the streets of Bombay held by disgruntled satellite equipment dealers. Just which satellite system will win this Hindi version of Star Wars remains to be seen.

Meanwhile, Shinawatra has enjoyed some success in leasing C-band transponders to Indian customers. On August 22, 1997, Shinawatra Satellite announced that four Indian companies had signed up for extended C-band leases on the Thaicom 3 satellite's Asian regional beam. The Indian broadcasters, which include Raj Television Network Ltd., UB Network (Bangalore) Ltd., Punjap Television Ltd., and Continental Television Ltd., are now using Thaicom 3 as well as the uplinking and tape replay services of the new Thaicom teleport and DTH centre located in Pathumthani province, Thailand.

As version 1.0 of the Asia/Pacific SATELLITES ON DISK Library was being compiled, Shinawatra was conducting tests of a new digital C-band service to be offered on Thaicom 3's semi-global C-band beam. What's more, Vietnam TV (TV) also has appeared in tests on another C-band transponder. Refer to the latest version of the SATELLITES ON LINE analogue TV and digital TV pages for further information.

Customer	Starting Date	Polarisation	Frequency (GHz)
Raj Television Network Ltd.	August 14, 1997	Vertical	3.625 - 3.643
UB Network (Bangalore) Ltd.	August 17, 1997	Vertical	3.607 - 3.625
Punjab Television Network	August 17, 1997	Vertical	3.527 - 3.536
Continental Television Ltd.	August 21, 1997	Vertical	3.587 - 3.603
Continental Television Ltd.	October 1, 1997	Vertical	3.567 - 3.583