GRAPH-BASED ARRAY SIGNAL DENOISING FOR PERTURBED SYNTHETIC APERTURE RADAR

摘要

A radar image processing device is provided for generating a radar image from a region of interest (ROI). The radar image processing device receives transmitted radar pulses and radar echoes reflected from the ROI at different positions along a path of a moving radar platform and stores computer- executable programs including a range compressor, a graph modeling generator, a signal aligner, a radar imaging generator and a focused image generator. The radar image processing device performs range compression on the radar echoes by deconvolving the transmitted radar pulses and a radar measurement to obtain frequency-domain signals, generate a graph model represented by sequential positions of the moving radar platform and a graph shift matrix computed using the frequency-domain signals, iteratively denoise and align the frequency-domain signals to obtained denoised data and time shifts by solving a graph-based optimization problem represented by the graph model, wherein the approximated time shifts compensate phase misalignments caused by perturbed positions of the moving radar platform, and perform radar imaging based on the denoised data and the estimated time shifts to generate focused radar images.