Patent ID: 7720232

Claim:
A system comprising: a memory that stores program instructions; and a processor configured to read and execute the program instructions from the memory, wherein the program instructions are configured to direct the processor to: operate on samples of a digital output signal to determine samples of a digital correction signal, wherein the output signal samples are directed to an output channel for transmission from a speaker; and supply the digital correction signal samples to a first digital-to-analog converter for conversion into an analog correction signal; a subtraction circuit configured to generate a difference signal which is a difference between a first analog signal provided by a microphone and the analog correction signal, wherein the analog correction signal is an estimate of a contribution to the first analog signal due to a direct path transmission between the speaker and the microphone; wherein the program instructions are further configured to direct the processor to: receive a digital input signal derived from the difference signal; and perform acoustic echo cancellation on the digital input signal to obtain a resultant signal, wherein the acoustic echo cancellation is configured to remove contributions to the digital input signal due to reflected path transmissions between the speaker and the microphone.