The invention provides a
satellite communication
system based on Beidou RDSS. The
satellite communication
system specifically comprises a receiving channel and a transmitting channel. A receiving channel adopts a low-
intermediate frequency structure, an antenna receives a
radio frequency signal, the
radio frequency signal is directly down-converted into a low-
intermediate frequency signal through a mixer, and then the low-
intermediate frequency signal is converted into a
baseband signal through an analog-to-
digital conversion chip. The
system adopts a low-intermediate frequency structure and uses primary
frequency mixing, so that compared with secondary
frequency mixing of a superheterodyne structure, the system has the advantages of simple link, low cost, low
power consumption, high integration and the like. Meanwhile, the system is down-converted to low-intermediate frequency, and low-intermediate frequency signals are far away from
direct current, so that the problems of
direct current offset,
flicker noise and the like of the system are solved. A transmitting channel adopts a direct
frequency conversion structure, and a
baseband signal skips an intermediate frequency stage through a
frequency mixer and is directly up-converted to a
radio frequency signal transmitted by an antenna. The system not only ensures the advantages of simple link, low cost, low
power consumption, high integration and the like of the system, but also improves the stray problem of signals transmitted by the system.