FPGA multi-filter system for speech enhancement via multi-criteria optimization

•We study the signal enhancement problem.•We propose a multi-filter system.•We study the multi-criteria design of the system.•We propose an implementation of the system with an FPGA embedded system.

Speech is the main medium for human communication and interaction. Apart from the traditional telephones, more and more applications come with speech interfaces, which use speech signal as an input for various purposes. However, many of these applications might fail to perform in noisy environments as the signal-to-noise ratio (SNR) degrades. Two important measures for any speech enhancement algorithm are noise suppression and speech distortion. Naturally, different speech enhancement algorithms will have different trade-offs. Moreover, depending on the environment, it is possible that one algorithm will outperform the others in some respects. This paper proposes a multi-filter system, which has the capability of continually adjusting the noise suppression level and the speech distortion level in a Pareto fashion. Moreover, we show that the system works under a variety of noisy environments and we obtain the efficient frontier of the combined filters for each background noise. Because the multi-filters are adapting in parallel, the final system can be implemented on FPGA efficiently.

Graphical abstractSpeech is the main medium of communication. Besides classical telephones, many communication tools came into existence, yet most of them perform poorly in noisy environments as the signal-to-noise ratio (SNR) degrades. Noise suppression and speech distortion help ease such shortcomings. Depending upon the environment, a specific algorithm holds good. A multi-filter system capable of subduing the disturbances is described. It works under various noisy environments employing multiple filters in parallel and can be implemented on FPGA. Figure optionsDownload full-size imageDownload as PowerPoint slide