SPATIAL CROSS-SPECTRA OF AMBIENT SEA NOISE FIELD

The general expression of the spatia lcross-spectral density function of ambient sea noise is developed, based on the theory of local spectrum of underwater ambient noise field presented by Xu Zhenyong (1977). Spatial cross-spectra of several typical cases are calculated. The resultant expression for deep-sea model with the uniform sound velocity profile is consistent with that developed by Cron and Sherman (1962, 1965) except for an additional term which is due to inhomo-geneous plane waves and can be neglected when the depth of receivers is much greater than the distanse separating the receivers. Finally, the comparison of some theoretical calculations and earlier obtained experimental data is also given.