A Massively Parallel Digital Processor for Spotlight Synthetic Aperture Radar

Abstract

Near-real-time digital formation of large synthetic aper ture radar (SAR) images requires the computational throughput that only a dedicated special processor or a massively parallel computer can offer. This article documents the implementation of digital spotlight SAR processing components on three commercially avail able massively parallel computers: the Connection Ma chine (CM-2), the nCUBE 2, and the Intel iPSC/860. The three basic spotlight SAR processing components, the polar reformatter, the two-dimensional fast Fourier transformation, and autofocus, are briefly discussed to provide a technical background for the implementation issues that apply to massively parallel computers. As pects of the SAR components that can exploit features of a SIMD or MIMD architecture are also presented. Finally, timing test results on various computers are provided for evaluation and comparison.

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