FIELD: radio engineering. SUBSTANCE: echo suppressor has first filter which produces first-filter factors, first echo-signal evaluation signal based on first-filter factors updates first-filter factors in response to first-filter control signal. First adder subtracts first echo signal evalutation signal from combined signal of return channel and echo-signal receiving channel followed by generation of first residual echo-signal. Second filter produces second-filter factors, generates second echo-signal evaluation signal based on second-filter factors, and updates second-filter factors in response to second-filter control signal. Second adder subtracts second echo-signal evaluation signal from combined signal to generate second residual echo-signal and to ensure passage of second residual echo-signal through return channel. Control device functions to determine one of set of control states basing on receiving-channel signal, combined signal, and first and second residual echo-signals; first control state shows that receiving-channel signal level is higher than first desired energy level; when device is in its first control state, it will produce first control signal and second one at the moment when at least first ratio of first residual echo-signal energy to combined signal energy or second ratio of second residual echo-signal energy to combined signal energy exceeds desired level. EFFECT: provision for suppressing receiving-channel echo-signal in return-channel signal where echo-signal channel is used to combined receiving-channel echo-signal and return-channel input signal. 10 cl, 16 dwg, 1 tbl
