Self-adaptive suppression method of time varying sinusoidal interference in audio signals

Abstract

The invention discloses a self-adaptive suppression method of time varying sinusoidal interference in audio signals. The method includes the following steps: step one, inputting original audio signals and performing AD conversion on the original audio signals; step two, calculating preliminary frequency of sinusoidal interference signals in the audio signals through a self-adaptive notch filter algorithm; step three, calculating amplitude, phase and accurate frequency of the sinusoidal interference signals in the audio signals through a least mean square (LMS) gradient descent algorithm; step four, deciding credibility of the sinusoidal interference signals through a decision algorithm, turning to step five if the credibility is true, and outputting the audio signals directly if the credibility is false; and step five, subtracting the calculated sinusoidal interference signals from the audio signals so as to obtain and output the audio signals after interference suppression. The self-adaptive suppression method of the time varying sinusoidal interference in the audio signals has the advantages of being capable of suppressing the time varying sinusoidal interference, insensitive to preliminary value setting, high in convergence rate, simple in calculation, high in quality, good in accuracy and stability, and suitable for processing all audio signals.

Description

technical field [0001] The invention relates to the field of digital audio processing, in particular to an adaptive suppression method for time-varying sinusoidal interference in audio signals. Background technique [0002] The audio pickup process often encounters interference from time-varying sine or cosine signals. For example, the phenomenon of power frequency interference, the self-excited oscillation phenomenon due to acoustic feedback, and the interference of specific noise frequencies (such as the roar of cars and airplanes) and so on. Sine interference and cosine interference are only π / 2 in phase difference, so they are collectively called sine interference. In most cases, sinusoidal interference is time-varying and belongs to the category of non-stationary signals. The energy or amplitude of the interference signal is usually large, the signal-to-noise ratio is very low, and the signal is usually submerged in the interference. [0003] One of the keys to suppr...

AI Technical Summary

Problems solved by technology

[0008] The present invention mainly solves the technical problem existing in the prior art that it is difficult to quickly and accurately suppress the sinusoidal interference in the sound signal, and provides a method that is insensitive to initial value setting, fast in convergence speed, simple in calculation, high in quality, accurate and stable. An Adaptive Suppression Method for Time-varying Sinusoidal Interference in Good Audio Signals

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