浅海运动噪声源的声场统计特性及其对噪声测距声呐信号处理的影响  

STATISTIC PROPERTIES OF THE NOISE FIELD OF MOVING SOURCE IN SHALLOW WATER AND ITS EFFECTS ON SIGNAL ROCESSING FOR THE NOISE RANGING SONAR

作　　者：许祯镛 

机构地区：[1]中国科学院声学研究所

出　　处：《声学学报》1989年第4期294-304,共11页Acta Acustica

摘　　要：本文研究了运动噪声源在分层统计不均匀的媒质中(并考虑随机起伏边界的影响)噪声场时空相关函数的性质。 理论与大量海上实验都证明了,传播的多径效应使相关函数拖散,媒质的折射率起伏与边界起伏引起相关函数的起伏。而噪声源的运动对实时相关器的输出的影响等效于低通滤波器并附加时空相关函数的漂移。相关函数的这些性质大大降低了噪声测距声呐系统的信号处理增益。 相关函数的起伏和畸变,使噪声测距难于实现。为此,本文提出了小间距大跨度的四点阵空间相关测距与二次相关信号处理技术,大大地克服了上述诸因素的影响。本文还对内波引起的长周期大时延起伏的二次相关函数的输出,提出了有限记忆类卡尔曼滤波处理方法,使噪声测距声呐最终实现有效的准确测距与跟踪。In this paper the properties of space-time correlation function of the noise field of moving source in layered statistic inhomogeneous medium are studied and the effects of random fluctuating boundary are considered as well. It has been shown, theoretically and experimentally multi-path propagating effects cause the dispersion of the correlation function and fluctuations of the medium refraction index and the boundary cause the fluctuation of it. The effect of the movement of the noise source on the output of real-time correlator is equivalent to a low-pass filter added the drift of space-time correlation function. These properties of the correlation function cause grave degradation of the signal processing gain of noise ranging sonar system. The fluctuation and the distortion of correlation function made it difficult to realize the noise ranging. So, in this paper, a method of space correlation ranging by a linear array of four points with short separation and long span and a technique of dual-correlation signal processing are presented by this, the influences of preveiously mentioned factors are greatly overcomed. Futhermore, for the long period and large delay fluctuation of the dualcrrelation function output caused by internal wave, a method of limited memory quasi-Kalman filtering is developed and the effective accurate ranging and tracing of noise ranging sonar are able to be realized finally.

关 键 词：运动噪声源 声场 噪声 声呐 海洋 

分 类 号：P733.22[天文地球—物理海洋学]