Adaptive echo compensator for asynchronous CW system - has frequency corrector containing two multipliers, Hilbert transformer, adder and voltage controlled oscillator

摘要

The echo compensator has a frequency corrector (FR) containing two multipliers (M1, M2) whose outputs are added (A1) to produce a frequency corrected signal. The line in the direction (4) leading to the remote subscriber's coupler (G) is connected one way directly to one input of the second multiplier and the other way via a Hilbert transformer (H) to one input of the first multiplier. The remaining to inputs of the two multipliers are connected to two outputs of a voltage controlled oscillator (VCO). These two outputs deliver sine and cosine signals.