ESTIMATION AND SUPPRESSION OF HARMONIC LOUDSPEAKER NONLINEARITIES

摘要

Described is a harmonic echo power estimator configured to estimate power of echo generated by harmonic loudspeaker nonlinearities in a user equipment having an echo path between a loudspeaker input and a microphone output. This estimator includes a frequency band mapper (40) configured to map each frequency band in a set of loudspeaker output signal frequency bands (b isp ) into a corresponding array of loudspeaker input signal frequency bands (b(b isp ,k)), where each frequency band in the set is mapped into several frequency bands in the corresponding array. A power estimator (42) is configured to determine a power estimate (P x (b(b isp ,k))) of each input signal in each array of frequency bands. A power estimate combiner (44) is configured to combine determined power estimates (P x (b(b isp ,k))) in each array of frequency bands into a corresponding estimate (P x, nl (b isp )) of loudspeaker input power generating harmonic loudspeaker nonlinearities. A power estimate transformer (46) is configured to transform the estimates of loudspeaker input power across the echo path (EP) into power estimates (P s, nl (b)) of the echo generated by the harmonic loudspeaker nonlinearities.