SAR narrowband radio frequency interference suppression method based on Bayesian estimation

Abstract

The invention belongs to the technical field of radar signal processing, and discloses an SAR narrowband radio frequency interference suppression method based on Bayesian estimation. The method comprises the steps of introducing an interference detection method based on kurtosis, and carrying out interference judgment on an original echo; by utilizing sparse prior information of a narrowband RFI,introducing a probability density distribution parameterization model for sparse constraint of the narrow-band RFI, and establishing an SAR echo probability statistical model with narrowband radio frequency interference; estimating model parameters by utilizing Bayesian estimation and the maximum posterior probability, and accurately reconstructing the narrowband RFI; and obtaining echo data afterinterference suppression through data domain interference cancellation. According to the method, the sparse prior parameterization model of the narrowband RFI is fully utilized, and the narrowband RFI is reconstructed with high accuracy through Bayesian estimation and the maximum posterior probability; and the influence of interference signals on SAR imaging quality is reduced, and the survivability of an SAR system in a complex electromagnetic environment is improved.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, and in particular relates to a Bayesian estimation-based synthetic aperture radar (Synthetic Aperture Radar, SAR) narrow-band radio frequency interference suppression method, which is used to weaken the impact of narrow-band radio frequency interference (Radio Frequency Interference, RFI) on SAR imaging quality Significantly enhance the ability of SAR image interpretation, and improve the information acquisition ability of SAR in complex electromagnetic environments. Background technique [0002] Because SAR has the advantages of all-day, all-weather, long range and high-resolution two-dimensional imaging, SAR is currently an important means of active microwave remote sensing. However, with the wide application of SAR, SAR is threatened and challenged more and more seriously by the interference in the complex electromagnetic environment. In particular, the extensive use of radiat...

AI Technical Summary

Problems solved by technology

This method models the narrowband RFI as a combined model of multiple single-frequency components, and reconstructs the narrowband RFI by the least square method, but this method is essentially a maximum likelihood solution under Gaussian noise

Since there is no constraint on the form of narrowband RFI, it is prone to estimation errors in the case of low interference-to-signal ratio

Due to the rapid development of compressed sensing theory, K.Shuya et al. used compressed sensing theory to reconstruct and suppress narrowband RFI with high probability, but this method only considered the sparse prior information of narrowband RFI, but its key parameters such as sparsity It needs to be acquired a priori or manually selected. However, it is difficult to determine key parameters such as narrowband RFI sparsity under different interference-to-signal ratios

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