Method and system for reducing impulsive noise disturbance

摘要

FM and AM receivers in car environments require a noise blanker circuit or method to reduce the audible disturbances generated by impulse noise, such as ignition noise, in the audio signal. The invention proposes a combination of time-domain and frequency-domain processing to reduce the audible distortion. The time-domain processing interpolates the signal during the impulse noise bursts, and the frequency-domain processing disperses the remaining signal distortion over time, or relocates it to positions in time where it is attenuated by a windowing technique.

主权项

1. An audio processing system comprising:
a detector for detecting the presence of impulse noise; a processor, processing an audio input signal in the time domain in dependence on a detected presence of impulse noise; a first device, transforming the audio input signal between the time domain and the frequency domain; extractor, extracting the magnitude and phase spectra of the frequency domain signal; modifier, modifying at least parts of the phase spectrum in dependence on the detected presence of impulse noise; combiner, combining the magnitude spectrum and modified phase spectrum; and second device, transforming the combined signal between the frequency domain and the time domain.