Research on influencing factors and compensation methods of the azimuth
cutoffwavelength based on multiview synthetic aperture radar wave
synchronizationdata
Abstract
Due to the nonlinear effect of velocity bunching modulation, azimuth
cutoff occurs when
waves are propagating along the azimuth direction. This is an inherent
disadvantage of synthetic
aperture radar (SAR) wave observation and makes it impossible to obtain
complete wave
information. For a single SAR observation, the problem of the azimuth
cutoff wavelength of ocean
waves can be solved to some extent by the cooperative observations of
SAR satellites. It is necessary to use multiple SAR satellites to
achieve simultaneous observation of the same ocean area to obtain
multiview SAR ocean wave synchronization data. At present, it is
impossible to acquire multiview synchronization data based on in-orbit
SARs. Therefore, this paper first carried out imaging simulations of
multiview SAR ocean wave synchronization data. Second, the MPI method
was used to obtain the optimum wave spectrum of synchronous data. The
influencing factors of the azimuth cutoff wavelength were analyzed by
using the measured SAR data. Based on the analysis results, a new method
of multiview wave spectrum data fusion is proposed to realize azimuth
cutoff compensation. The azimuth cutoff compensation effect is evaluated
by using the inversion results of the azimuth cutoff before and after
spectral data fusion, the significant wave height and the mean wave
period. The results show that the azimuth cutoff compensation method
established in this paper can solve the problem of information loss
caused by azimuth cutoff to some extent, improve the ability of SAR wave
observation, and lay a foundation for SAR wave operational observation.