Echo processing apparatus

An echo processor comprising:

• a high-pass filter suppressing a low-frequency component in a received signal in digital form;
• a D/A converter converting the low-frequency component passed through the high-pass filter to a sound signal;
• a speaker outputting an acoustic based on the sound signal;
• a microphone having a possibility to input an echo of the acoustic outputted from the speaker;
• an A/D converter converting the sound signal outputted from the microphone to a digital signal;
• echo canceller means generating a pseudo echo signal based on a low-frequency suppressed received signal obtained through the high-pass filter and generating a transmission signal by subtracting the pseudo echo signal from the digital signal outputted from the A/D converter;
• and
• double-talk detector means extracting a low-frequency component in the digital signal outputted from the A/D converter, performing a double-talk judgment based on the low-frequency component, and controlling to halt and start the update of a filter coefficient of the echo canceller means.