The impact of ocean stratification characteristics on the identifiability of internal wave wakes in synthetic aperture radar images

Objectives Aiming at the identifiability problem of underwater vehicle trails in synthetic aperture radar (SAR) images in a density stratified environment, a theoretical solution model and a quantitative analysis method are established.

Methods Based on the statistical information of ocean stratification characteristics, a theory of internal waves induced by equivalent sources of moving mass and momentum is designed. The modulated wave spectrum of each statistically independent sea surface unit and the corresponding intensity distribution mapped in SAR images are calculated, and then the texture feature information of internal wave trails in the images is extracted based on the gray level co - occurrence matrix.

Results The results show that under specific parameter conditions, the identifiable interval of internal wave trails in SAR images is when the maximum buoyancy frequency is greater than 0.02 rad/s and the corresponding depth is less than 100 m.

Conclusion This method can effectively calculate and analyze the identifiability of internal wave trails in any density stratified environment and provides a basis for underwater target detection.