Multi-channel echo cancelling method and a device thereof
AssigneeNEC Corporation
InventorAkihiro Hirano
Life of this patent
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Abstract
The present invention relates to a multi-channel echo cancelling art enabling proper operation even if using a microphone not generating propagation delay difference between channels. The present invention comprises: a step of calculating a power of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest power; a step of generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of the reception channels based on a reception signal of the reception channel selected in the previous step; and a step of cancelling the echoes from mixed signals in which the echoes are mixed by subtracting the echo replicas from the mixed signals.
Claims33
A multi-channel echo cancelling method comprising:
- a step of calculating a power of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest power;
- a step of generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of said reception channels based on said reception signal of the reception channel selected in the previous step for each reception channel;
- and
- a step of cancelling said echo from said mixed signal by subtracting said echo replica from said mixed signal for each reception channel.
A multi-channel echo cancelling method comprising:
- a step of calculating an absolute value of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest absolute value;
- a step of generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of said reception channels based on said reception signal of the reception channel selected in the previous step for each reception channel;
- and
- a step of cancelling said echo from said mixed signal by subtracting said echo replica from said mixed signal for each reception channel.
A multi-channel echo cancelling device comprising:
- a reception signal selection means for calculating a power of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest power;
- a means for generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of said reception channels based on said reception signal of the reception channel selected by said reception signal selection means for each reception channel;
- and
- a means for cancelling said echo from said mixed signal by subtracting said echo replica from said mixed signal for each reception channel.
A multi-channel echo cancelling device comprising:
- a means for calculating an absolute value of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest absolute value;
- a means for generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of said reception channels based on said reception signal of the reception channel selected by said reception signal selection means for each reception channel;
- and
- a means for cancelling said echo from said mixed signal by subtracting said echo replica from said mixed signal for each reception channel.
A multi-channel echo cancelling device comprising:
- a plurality of power calculation means, one-to-one corresponding to each reception signal, for calculating a power of reception signal of said reception channel;
- a reception channel selection means for selecting a reception channel having the biggest power of reception signal based on the calculation result from said power calculation means;
- a selection means for receiving reception signals of reception channels and outputting a reception signal of a selected reception channel based on the selected result by said reception channel selection means;
- a plurality of adaptive filters, one-to-one corresponding to mixed signals in which echoes generated by propagation of reception signals of said reception channels are mixed, for generating echo replicas corresponding to said echoes based on a reception signal supplied by said selection means;
- and a plurality of subtraction means, one-to-one corresponding to said mixed signals, for outputting a result by subtracting said echo replicas from said mixed signals.
Dependencies are inferred from the claim text.