The Development Of Satellite Communication IF Signal Distributor

In satellite communication system, FDMA (frequency division multiple access) would remain the most widely used in the future because of its mature technique, simplicity and relatively low cost in applications. The primary technique of FDMA is frequency division multiplexing. The base-band signals are modulated onto various frequency carriers by modulator, and then multiplexed together by power divider/combiner. This method has two deficiencies in engineering application: one is that every inputs/outputs of power divider/combiner must be matched, and the link attenuation is very large when the number of outputs of the divider is excessive; the other is the need to control the carrier powers so that they are same at the satellite input, however, they are adjusted by mechanical variable attenuator when it go beyond the modulator's adjustable range, but it will interrupt the communication signal while adjusting.To resolve these deficiencies, we developed the satellite communication IF signal distributor. It adjusts the carrier powers through digital controlled electronic attenuator, performs power division/combination by adder circuits designed with microwave amplifier, and every circuits board of the equipment can be plug in or out while the electric supply is applied. So, the equipment not only resolved the . deficiencies but also suitable for satellite communication application.The primary technique of developed the satellite communication IF signal...