水声信号的窄带滤波研究

研究一种用于有色噪声背景下接收水声信号的窄带滤波方法。它用白化滤波器实现有色噪声的匹配滤波。该滤波电路具有优良的选频能力,抗干扰性强,功耗极低,较好地解决了水下信息传输中存在的通道之间频率间隔小、信号微弱、易受噪声干扰、用电池供电而要求工作时间长等问题。采用这种窄带滤波方法的水声接收机具有结构简单、性能稳定、对弱信号检测能力强等优点,增大了定位声纳的作用距离。

A narrowband filter(NF) for receiving the CW pulse in the water under colored noise is studied. The NF realizes matching filtering under colored noise by a whitening filter which changes colored noise into the white noise. The NF circuit has excellent capabilities of narrowband filtering, anti-interfering, and low power. In its present form, it can be used to solve many problems of underwater acoustic system, such as small frequency interval, slight signal, easily interfered by noise, short work hours and so on. In addition, the receiver on the basis of this method is simple, stable, and detects slight signal very well. The experiment results indicated that this method can cancel the interference and defects the signal even if SNR is decreased to- 14dB.