Patent ID: 6868158

Claim:
An echo processor comprising: a high-pass filter configured to suppress a low-frequency component in a received signal in digital form; a D/A converter configured to convert the low-frequency suppressed received signal obtained through the high-pass filter to a sound signal; a speaker configured to output an acoustic based on the sound signal; a microphone configured to input an echo of the acoustic output from the speaker; an A/D converter configured to convert the sound signal output from the microphone to a digital signal; an echo canceller configured to generate a pseudo echo signal based on the low-frequency suppressed received signal obtained through the high-pass filter and configured to generate a transmission signal by subtracting the pseudo echo signal from the digital signal output from the A/D converter; and a double-talk detector configured to receive the low-frequency suppressed received signal obtained through the high-pass filter and configured to perform a double-talk judgment based on the low-frequency suppressed received signal obtained through the high-pass filter.