A sea surface motion ship air-time variable parameter equalization imaging method based on distance phase difference

Abstract

This application discloses a space-time-varying parameter equalization imaging method for ships moving on the sea surface based on range-phase difference, belonging to the field of radar target imaging technology. The method includes: constructing an azimuth frequency domain space-varying window to extract space-varying signals from radar echo signals by utilizing the bandwidth characteristics of space-varying phase errors; performing phase difference processing on space-varying signals of different range units to eliminate space-invariant phase errors and converting the space-varying phase errors into a space-invariant form; estimating and compensating the converted phase error using a self-focusing algorithm, iteratively narrowing the space-varying window and extracting the space-varying signals again, repeating the estimation and compensation process until the number of iterations reaches a preset threshold, and outputting the final image. This application can achieve high-precision estimation of generalized space-varying and space-invariant phase errors, effectively solving the image defocusing problem caused by complex rotational motion of ship targets.

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