Sidetone level reduction circuit and method

摘要

A sidetone level reduction circuit for reducing the sidetone level in digital cordless telephones incorporating continuously variable slope delta modulator/demodulator (CVSD) digital to analog technology is disclosed comprising a CVSD encoder for converting an analog voice signal to a digital signal, a CVSD decoder for converting a digital signal to an analog signal voice signal, and coupling means connecting the coincidence output of the CVSD encoder and the coincidence output of the CVSD decoder in a manner such that the coincidence output of the CVSD decoder can affect the CVSD encoder but the CVSD encoder cannot affect the CVSD decoder.