The f.m. signal from the satellite is transposed in frequency in the receiver and demodulated. At least one three-section Chebyshev filter tuned to the received channel of the transposed f.m. signals is provided after the frequency converter but before the f.m. demodulator; its bandwidth has a specified value; the filter attenuation ripple is between 0.5 and 1 db; in order to reduce filter distortions and to improve transmission quality, a pre-emphasis network is provided at the transmission end, and a de-emphasis network at the receiving end.
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