A New Acoustic Feedback Control Technique With Low Computational Cost Requirement

Abstract

Traditional room modelling acoustic howling control technique have respectable sound quality indices and a potentially infinite Maximum Stable Gain (MSG) Increase figure but their computational complexity requirements is high. This makes them less attractive for acoustic howling control in long acoustic path applications. A new technique that requires only a single multiplication operation for its implementation is developed in this paper. The technique is modelled and then simulated in a MATLAB® environment with both speech and audio input signal to obtain the Maximum Stable Gain (MSG) Increase and sound quality figures. For speech signal and audio signal, a MSG Increase figure of 8.698 dB and 8.787 dB were achieved when the feedback step size is 0.25 and the loop correction frequency is equal to the signal frequency respectively. For both speech and audio signals, the average signal quality figures, on a scale of 0 - 5, are respectively 2.2636 and 1.15, indicating poor signal quality. Thus, the developed technique has reduced computational complexity requirement, a good MSG Increase figure at the expense of poor sound quality.