| 摘要 |
PURPOSE: An echo cancellation device in a switching system and a method thereof are provided to cancel echoes generated when configuring speech channels in every speech channel in real time, thereby improving speech quality. CONSTITUTION: An originating subscriber attempts a call and a speech channel with an incoming subscriber is set(S100). When an incoming exchange delivers the first ring signal to the incoming subscriber, an originating exchange connects an echo characteristic measuring unit to the current channel through a switching unit, to measure a round trip delay time and a singing margin of an echo, which are echo characteristics for a connection path(S200). When the round trip delay time and the singing margin are completely measured, the echo characteristic measuring unit is released and an echo cancellation unit is connected to the corresponding channel through the switching unit, to set an echo characteristic value of the echo cancellation unit by using the measured round trip delay time and the singing margin(S300) and cancel the echo of the corresponding speech channel(S400).
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