Patent ID: 8694059

Claim:
A mobile communication device, comprising: a housing; a speaker provided in the housing for outputting an incoming voice according to an incoming voice signal; a microphone provided in the housing for receiving an outgoing voice and outputting an outgoing voice signal in response to reception of the outgoing voice; a detecting unit for detecting vibration of the housing and outputting a housing-vibration signal indicating the vibration of the housing; a processing unit for performing echo cancellation to the outgoing voice signal based on the incoming voice signal and the housing-vibration signal; and a receiver for outputting the incoming voice according to the incoming voice signal, wherein the processing unit is configured to switch between a normal call mode and a hands-free call mode; the normal call mode is a mode in which the incoming voice is output from the receiver and the echo cancellation is performed to the outgoing voice signal based on the incoming voice signal; the hands-free call mode is a mode in which the incoming voice is output from the speaker and the echo cancellation is performed to the outgoing voice signal based on the incoming voice signal and the housing-vibration signal; and the processing unit is configured to add a signal obtained by inverting a phase of the incoming voice signal to the outgoing voice signal to perform the echo cancellation of first echo when the incoming voice is output from the speaker or the receiver, and to add a signal obtained by inverting a phase of the housing-vibration signal to the outgoing voice signal to perform the echo cancellation of second echo when the incoming voice is output from the speaker.