利用波导不变性提高声场的水平纵向相关

基金项目:

国家自然科学基金资助项目(10234050)

详细信息

Improvement of the longitudinal correlations of acoustical field by using the waveguide invariance

1 National Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences Beijing 100080;
2 Graduate University of Chinese Academy of Sciences Beijing 100080

摘要: 简正波干涉可以引起声场的水平纵向相关下降,从而降低大孔径阵列信号处理的增益。基于声场的波导不变性,提出了信道中具有一定纵向间隔的两点的频率响应函数之间的线性相位关系。利用该线性相位关系,提出了一种适用于声源频谱缓变条件下提高声场水平纵向相关的频移补偿方法。浅海声学实验结果表明,该方法能使实验中水平阵接收信号的空间相关得到显著提高。

Abstract: Normal modes interference can result in longitudinal-correlation decreasing of the acoustical field in ocean waveguides, so it will lead to the gain decreasing of wide-aperture array. Based on the waveguide invariance, the linear phase relationship between the frequency response functions of the two points with certain longitudinal separation in a channel is put forward. With the linear phase relationship, a frequency-shift compensation method is proposed, which can be used to improve the longitudinal correlations of acoustical field.Results from a shallow-water acoustical experiment show that the spatial correlations of the signals received by the horizontal array can be improved significantly by the frequency-shift compensation method.