Beam forming and acoustic echo cancellation with mutual adaptation control

An audio conferencing system comprising:

• an adaptive beamforming module with a beamforming adaptivity and a beamforming adaptation state, wherein the adaptive beamforming module is configured to provide one or more beamforming status indicators that indicate the beamforming adaptation state, and wherein the adaptive beamforming module is configured to receive a plurality of input audio signals and to generate a beamformed audio signal based upon a combination of the plurality of input audio signals;
• an adaptive acoustic echo cancellation module with an acoustic echo cancellation (AEC) adaptivity and an AEC adaptation state, wherein the adaptive acoustic echo cancellation module is configured to provide one or more AEC status indicators that indicate the AEC adaptation state, and wherein the adaptive acoustic echo cancellation module is configured to receive the beamformed audio signal and to generate an echo-cancelled audio signal based upon the beamformed audio signal and a far-end audio signal;
• and
• wherein the adaptive beamforming module is configured to receive the AEC status indicators, to reduce the beamforming adaptivity when the AEC adaptation state is unsettled, and to restore the beamforming adaptivity when the AEC adaptation state is settled;
• wherein the adaptive acoustic echo cancellation module is configured to receive the beamforming status indicators, to increase the AEC adaptivity when the beamforming adaptation state is unsettled, and to restore the AEC adaptivity when the beamforming adaptation state is settled;
• wherein the adaptive acoustic echo cancellation module is configured to determine one or more AEC adaptation parameters based upon the beamforming status indicators, wherein the adaptive acoustic echo cancellation module is configured to generate the echo-cancelled audio signal additionally based upon the AEC adaptation parameters;
• wherein the adaptive acoustic echo cancellation module includes a primary echo removal filter and wherein one of the AEC adaptation parameters is a convergence rate of the primary echo removal filter.

A method of combined beamforming and acoustic echo cancellation in an audio conferencing system that includes an adaptive beamforming module and an adaptive acoustic echo cancellation module, the method comprising:

• receiving a first acoustic echo cancellation (AEC) status indicator from the adaptive acoustic echo cancellation module that indicates that the adaptive acoustic echo cancellation module is adapting to changed conditions;
• determining a beamforming modified-adaptation parameter based upon the first AEC status indicator;
• while the adaptive acoustic echo cancellation module is adapting to changed conditions as indicated by the first AEC status indicator, beamforming with the adaptive beamforming module based upon the beamforming modified-adaptation parameter;
• receiving a first beamforming status indicator from the adaptive beamforming module that indicates that the adaptive beamforming module is adapting to changed conditions;
• determining an AEC modified-adaptation parameter based upon the first beamforming status indicator;
• while the adaptive beamforming module is adapting to changed conditions as indicated by the first beamforming status indicator, echo-cancelling with the adaptive acoustic echo cancellation module based upon the AEC modified-adaptation parameter;
• receiving a second AEC status indicator from the adaptive acoustic echo cancellation module that indicates that the adaptive acoustic echo cancellation module is adapted to changed conditions;
• determining a beamforming nominal-adaptation parameter based upon the second AEC status indicator;
• while the adaptive acoustic echo cancellation module is adapted to changed conditions as indicated by the second AEC status indicator, beamforming with the adaptive beamforming module based upon the beamforming nominal-adaptation parameter;
• receiving a second beamforming status indicator from the adaptive beamforming module that indicates that the adaptive beamforming module is adapted to changed conditions;
• determining an AEC nominal-adaptation parameter based upon the second beamforming status indicator;
• and
• while the adaptive beamforming module is adapted to changed conditions as indicated by the second beamforming status indicator, echo-cancelling with the adaptive acoustic echo cancellation module based upon the AEC nominal-adaptation parameter.