Peterson P M, Wei S M, Rabinowitz W M, Zurek P M
Massachusetts Institute of Technology, Research Laboratory of Electronics, Cambridge.
Acta Otolaryngol Suppl. 1990;469:85-90.
We describe the results of computer simulations of a multimicrophone adaptive-beamforming system as a noise reduction device for hearing aids. Of particular concern was the system's sensitivity to violations of the underlying assumption that the target signal is identical at the microphones. Two- and four-microphone versions of the system were tested in simulated anechoic and modestly-reverberant environments with one and two jammers, and with deviations from the assumed straight-ahead target direction. Also examined were the effects of input target-to-jammer ratio and adaptive-filter length. Generally, although the noise-reduction performance of the system is degraded by target misalignment and modest reverberation, the system still provides positive advantage at input target-to-jammer ratios up to about 0 dB. This is in contrast to the degrading target-cancellation effect that the system can have when the equal-target assumption is violated and the input target-to-jammer ratio is greater than zero.
我们描述了作为助听器降噪设备的多麦克风自适应波束形成系统的计算机模拟结果。特别值得关注的是，该系统对违反目标信号在各麦克风处相同这一基本假设的情况的敏感性。该系统的双麦克风和四麦克风版本在模拟消声和适度混响环境中进行了测试，测试对象包括一个和两个干扰源，以及与假定的正前方目标方向的偏差。还研究了输入目标与干扰源比率和自适应滤波器长度的影响。一般来说，虽然系统的降噪性能会因目标未对准和适度混响而降低，但在输入目标与干扰源比率高达约0 dB时，该系统仍具有积极优势。这与当违反等目标假设且输入目标与干扰源比率大于零时系统可能产生的目标抵消效果恶化形成对比。
