Synthetic Aperture Radar Signal Processing with MATLAB Algorithms

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GENERIC SYNTHETIC APERTURE RADAR

Introduction

Synthetic aperture radar (SAR) is an imaging modality that addresses the general problem of forming a target region reflectivity function in the multidimensional spatial domain of range, cross-range, and altitude (x, y, z). Our present discussion is simplified by combining the range and altitude variables to form the slant-range domain, that is, see the discussion on the radar radiation pattern in the three-dimensional spatial domain in Section 3.2. Thus the imaging problem is formulated in the two-dimensional slant-range and cross-range (x_s, y) domains. For convenience we call the imaging plane range and cross-range, and identify it as (x, y).

SAR image formation is based on a two-dimensional signal theory which heavily benefits from the range imaging and cross-range imaging principles of Chapters 1 and 2. The major difference is that we do not assume that the targets in the imaging scene are at a fixed range or cross-range. The target region is assumed to be composed of stationary targets located at unknown coordinates (x_n, y_n), n = 1, 2, ....

•  While we use a discrete model to represent the target area, our results are also applicable in the case of a continuous target model. The use of a discrete target model is for notational convenience.

The transmitting/receiving radar is mounted on an aircraft and takes on the coordinates ...