Thaicom is the name of a series of communications satellites operated from Thailand, and also the name of Thaicom Public Company Limited, which is the company that owns and operates the Thaicom satellite fleet and other telecommunication businesses in Thailand and throughout the Asia-Pacific region. The satellite projects were named Thaicom by the King of Thailand, His Majesty the King Bhumibol Adulyadej, as a symbol of the linkage between Thailand and modern communications technology.

BSAT-1a was a geostationary communications satellite designed and manufactured by Hughes (now Boeing) on the HS-376 platform. It was originally ordered and operated by the Broadcasting Satellite System Corporation (B-SAT). It was used as the main satellite to broadcast television channels for NHK and WOWOW over Japan. It had a pure Ku band payload and operated on the 110°E longitude until it was replaced, along with its backup BSAT-1b, by BSAT-3a. On 3 August 2010, it was decommissioned and placed on a graveyard orbit.

The spacecraft was designed and manufactured by Hughes on the HS-376 satellite bus. This spin-stabilized platform had two main sections. One, the spinning section, was kept rotating at 50 rpm to maintain the attitude, and an unspun section was used by the payload to maintain radio coverage. The spinning section included the Star-30BP Apogee kick motor, most of the attitude control, the power subsystem, and the command and telemetry subsystems. The unspun section contained the communications payload, including the antennas and transponders.

It had a launch mass of 1,236 kg (2,725 lb), a mass of 723 kg (1,594 lb) after reaching geostationary orbit, and a 10-year design life. When stowed for launch, its dimensions were 3.15 m (10.3 ft) long and 2.17 m (7 ft 1 in) in diameter. With its solar panels fully extended it spanned 7.97 m (26.1 ft). Its power system generated approximately 1,200 Watts of power thanks to two cylindrical solar panels. It also had NiH2 batteries for surviving solar eclipses. It would serve along BSAT-1b on the 110°E longitude position for the B-SAT.

Its payload was composed of four active plus four spare Ku band transponders fed by a TWTA with an output power of 106 Watts. Its footprint covered Japan and its surrounding island.