The invention discloses a method of suppressing communication 
noise of 
baseband voice signals. At a transmitting end, the 
baseband voice 
signal band is divided into two sub bands; 
low pass filter processing and 
automatic gain control (AGC) constant amplitude 
processing are carried out on original voice signals, and the obtained signals are transmitted in the 
low frequency sub band; an original voice 
signal waveform envelope is extracted during an AGC process, and envelope signals are obtained and are subjected to 
frequency modulation and are transmitted in the 
high frequency sub band; during the AGC constant amplitude 
processing process, voiced-segment signals are subjected to 
amplitude compression processing and silent-segment signals are subjected to amplitude expansion processing, the 
signal amplitudes tend to be consistent, and the 
dynamic range becomes small; at a receiving end, a voice 
signal envelope is extracted through 
bandpass filtering and 
frequency modulation, and according to the envelope, low pass constant amplitude voice signals are subjected to waveform 
recovery; and the voice waveform 
recovery is an AGC inverse process. As the silent-segment signals are compressed and the voiced-segment signals are expanded, the silent-segment 
noise is thoroughly suppressed, the voiced-segment 
noise is covered by the voice signals, and good voice intelligibility can be obtained.