Maj Jean-Baptiste, Royackers Liesbeth, Moonen Marc, Wouters Jan
Lab Exp ORL, Katholieke Univesiteit Leuven, 3000 Leuven, Belgium.
IEEE Trans Biomed Eng. 2005 Sep;52(9):1563-73. doi: 10.1109/TBME.2005.851517.
In this paper, the first real-time implementation and perceptual evaluation of a singular value decomposition (SVD)-based optimal filtering technique for noise reduction in a dual microphone behind-the-ear (BTE) hearing aid is presented. This evaluation was carried out for a speech weighted noise and multitalker babble, for single and multiple jammer sound source scenarios. Two basic microphone configurations in the hearing aid were used. The SVD-based optimal filtering technique was compared against an adaptive beamformer, which is known to give significant improvements in speech intelligibility in noisy environment. The optimal filtering technique works without assumptions about a speaker position, unlike the two-stage adaptive beamformer. However this strategy needs a robust voice activity detector (VAD). A method to improve the performance of the VAD was presented and evaluated physically. By connecting the VAD to the output of the noise reduction algorithms, a good discrimination between the speech-and-noise periods and the noise-only periods of the signals was obtained. The perceptual experiments demonstrated that the SVD-based optimal filtering technique could perform as well as the adaptive beamformer in a single noise source scenario, i.e., the ideal scenario for the latter technique, and could outperform the adaptive beamformer in multiple noise source scenarios.
本文介绍了一种基于奇异值分解（SVD）的最优滤波技术在双耳背式（BTE）助听器中进行降噪的首次实时实现及感知评估。该评估针对语音加权噪声和多说话者嘈杂声，在单干扰声源和多干扰声源场景下进行。使用了助听器中的两种基本麦克风配置。将基于SVD的最优滤波技术与自适应波束形成器进行比较，已知自适应波束形成器在嘈杂环境中能显著提高语音清晰度。与两阶段自适应波束形成器不同，最优滤波技术在无需假设说话者位置的情况下工作。然而，该策略需要一个鲁棒的语音活动检测器（VAD）。提出了一种提高VAD性能的方法并进行了实际评估。通过将VAD连接到降噪算法的输出，能够很好地区分信号的语音加噪声时段和纯噪声时段。感知实验表明，基于SVD的最优滤波技术在单噪声源场景（即自适应波束形成器的理想场景）下的性能与自适应波束形成器相当，且在多噪声源场景下优于自适应波束形成器。
