Enhanced range-doppler algorithm for SAR image formation

Abstract

A Synthetic Aperture Radar (SAR) system is a powerful source of information due to its capability to operate day and night and in all weather conditions. It is essential for military and civilian purposes. Pulse-focusing is employed by the SAR system for achieving both long-range detection and fine-range resolution. The Range-Doppler Algorithm (RDA) is the most popular pulse-focusing technique for creating images from coherent SAR data. Pulse compression techniques for SAR signal processing targets seek to improve map resolution, lower peak power, and increase the Signal-to-Noise Ratio (SNR) of the detected object. This paper demonstrates an enhanced RDA algorithm that uses a modified pulse compression technique based on mismatched filter optimization where Quadratic Constrained Quadratic Program (QCQP) is used. The performance evaluation of the proposed method is performed using visual assessment and the standard image quality metrics peak-side-lobe-ratio (PSLR), impulse-response-width (IRW), and integrated-side-lobe-ratio (ISLR). Simulated and real SAR raw data are used for performance evaluation. The experimental results demonstrate the proposed method’s robustness, efficiency, and reliability in providing a higher-quality SAR image than the traditional RDA algorithm.

Enhanced synthetic aperture radar image autofocus and classification using 2D SARNet framework

“…2, the RDA starts with range compression along the range direction followed by a fast convolution. 15 This sequence encompasses a range FFT, multiplication with a matched filter in the frequency domain, and culminates in a range inverse fast Fourier transform (IFFT). 4 Assuming S 0 ðf t ; hÞ is the range FFT of s r and Gðf t Þ is the frequency domain matched filter, using the received demodulation signal provided by Eq.…”

“…14 1.1 Problem Definition SAR image formation is a complex process that involves several steps, from acquiring raw data to creating a coherent two-dimensional image of the scene area. 15 This process includes critical stages, such as range and azimuth compression, coupled with motion compensation to adjust for the movement of the platform. 1 The rapid development of SAR sensors that can cover very wide swaths generates a massive volume of data requiring extensive processing.…”