ECHO DETECTION METHOD, ECHO DETECTION SYSTEM, CALCULATION PART AND ECHO EXISTENCE DETECTION DEVICE, PARTICULARLY CONCERNED WITH DETECTING AN ECHO OF SUBSTANTIAL IN-SERVICE VOICE COMMUNICATION SYSTEM

摘要

PURPOSE: An echo detection method, an echo detection system, a calculation part and an echo existence detection device are provided to monitor an output part of a voice communication signal while monitoring an input part of the communication signal, and to time-array an output signal with an input signal to perform a correlation procedure, thereby deciding whether an echo exists within a voice communication channel. CONSTITUTION: When an output voice signal(212) is supplied to a communication network(104), an echo detector(204) monitors the signal(212), and supplies the signal(212) to a time array unit(304). The echo detector(204) monitors an input voice signal(216). A delay buffer(308) delays the time-arrayed output signal outputted from the time array unit(304). An output(316) from the delay buffer(308) is supplied to an adaptive filter(320). An adding block(324) receives the time-arrayed output voice signal(328) outputted from the adaptive filter(320), and receives the input voice signal(216) from the communication network(104). An output of the adding block(324) is an error signal(332). The error signal(332) is fed back to the adaptive filter(320).