A receiving antenna for direct satellite broadcasting

512-elements flat antenna

Fig.1 512-elements flat antenna

The start of research and development on receiving antennas for direct satellite broadcasting started in the year after NASDA launched No. 2 Broadcasting Satellite (BS-2a). Antennas for receiving direct satellite broadcasting must not only have high performance but also be mass produceable, and flat antennas have been under development as a replacement for conventional parabolic antennas. In May 1985, test broadcasting by NHK from broadcasting satellite “Yuri 2a” was started and became the world’s first satellite broadcasting enabling direst reception.

Although the efficiency of a flat antenna is lower than that of a parabolic antenna (30% compared to 60%), in 1987, a low-loss expanded polyethylene substrate was used in developing a 512-element flat antenna with efficiency of 60% and gain of 34 dBi. In July that year, full-time broadcasting by “Yuri 2b” (BS-2b) was started (note: subsequent NHK’s satellite broadcasting 1 =BS1). In the meantime, as for the parabolic antenna, development of a reflector usingfiber-reinforced plastic (FRP) was advanced. And in 1987, while it was under experimental testing, its technical specification was finalized.

In 1988, to further lower feeding loss, an active antenna—which is directly incorporated a low-noise amplifier into the antenna feeder—was developed.



Publications

[1] Murata T., Fujita M.、An Electromagnetically Coupled Active Flat Panel Antenna for DBS Reception、1991、21st European Microwave Conference, pp.1167-1172

Related Researches

Category

Broadcasting
(Radio and Optical Fiber Transmission)

Events in World

1987
Great Crash in New York Stock Exchange (Black Monday) happened.
1987
The Japanese National Railways was privatized and split up, and JR was inaugurated.
Page Top