Estimation and suppression of harmonic loudspeaker nonlinearities

摘要

A harmonic echo power estimator estimates power of echo generated by harmonic loudspeaker nonlinearities in a user equipment having an echo path between a loudspeaker input and a microphone output. The estimator includes a frequency band mapper that maps each frequency band in a set of loudspeaker output signal frequency bands into a corresponding array of loudspeaker input signal frequency bands, where each frequency band in the set is mapped into several frequency bands in the corresponding array. A power estimator determines a power estimate of each input signal in each array of frequency bands. A power estimate combiner combines determined power estimates in each array of frequency bands into a corresponding estimate of loudspeaker input power generating harmonic loudspeaker nonlinearities. A power estimate transformer transforms the estimates of loudspeaker input power across the echo path into power estimates of the echo generated by the harmonic loudspeaker nonlinearities.

主权项

1. A method of estimating power of echo generated by harmonic loudspeaker nonlinearities in a user equipment having an echo path between a loudspeaker input and a microphone output, said method comprising the steps of:
performing operations as follows on an echo canceller processor: mapping each frequency band in a set of loudspeaker output signal frequency bands (blsp) into a corresponding array of loudspeaker input signal frequency bands (b(blsp, k)), each frequency band in the set being mapped into several frequency bands in the corresponding array; determining a power estimate ({circumflex over (P)}x(b(blsp, k))) of each input signal in each array of frequency bands; combining determined power estimates ({circumflex over (P)}x(b(blsp, k))) in each array of frequency bands into a corresponding estimate ({circumflex over (P)}x,nl(blsp)) of loudspeaker input power generating harmonic loudspeaker nonlinearities; transforming the estimates ({circumflex over (P)}x,nl(blsp)) of loudspeaker input power across the echo path (EP) into power estimates ({circumflex over (P)}x,nl(b)) of the echo generated by the harmonic loudspeaker nonlinearities; and canceling echo in a microphone signal from the microphone responsive to the power estimates ({circumflex over (P)}{tilde over (s)},nl(b)) of the echo generated by the harmonic loudspeaker nonlinearities, to generate an echo canceled microphone signal.