The utility model discloses a
sidetone extraction module, which comprises a phase-locked loop and a digital
frequency synthesizer, wherein the phase-locked loop is used for receiving and tracking a sine distance measuring tone
signal which is received by a
satellite, and obtaining and outputting the frequency and phase of the sine distance measuring tone
signal, and the digital
frequency synthesizer is connected with the output end of the phase-locked loop through a circuit, and is used for regenerating and outputting the sine distance measuring tone
signal according to the outputted frequency and phase of the phase-locked loop. The
sidetone extraction module has the advantages that a digital
Costas loop with narrow
loop bandwidth, small loop
noise and high tracking accuracy is used for tracking the sine distance measuring tone signal generated by a
ground station to obtain the frequency and phase of the sine distance measuring tone signal, and then the sine distance measuring tone signal is duplicated by the digital
frequency synthesizer, and is sent to a downlink link modulator to modulate the phase of a downlink carrier, so the stability is high, the
resource consumption is decreased, the
system complexity is decreased, and the
resource consumption is further decreased; the tracking bandwidth is small, the tracking accuracy is higher, and the high-accuracy forwarding of the distance measuring signal is realized.