| 摘要 |
PROBLEM TO BE SOLVED: To provide an echo canceller that can minimize a line echo which is generated, when a telephone call is started. SOLUTION: This echo canceller has a pseudo-echo generation circuit 201 that has transmission characteristics being equivalent to the transmission path of a signal, where an echo is routed from a fixed line network and generates a pseudo-echo signal, by allowing a transmission signal from a mobile station at a transmission side to pass, a subtractor 202 that subtracts the pseudo-echo signal from a reception signal from a mobile station on reception side, an echo level detection circuit 204 that detects remaining echo according to the output of the subsractor, a nonlinear processor 206 that sets the output of the subsractor to a signal level, based on the given I/O characteristics, and an operational threshold-setting circuit 205 that sets the operational threshold of the nonlinear processor according to the detected output level of the echo level detection circuit.
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