Bistatic SAR/GISAR/FISAR Geometry, Signal Models and Imaging Algorithms

3

BSAR Waveforms and Signal Models

In this chapter, BSAR waveforms and signal models are presented. Short pulse signals, linear frequency modulated (LFM) and phase code modulated (PCM) waveforms and GPS (Global Positioning System) signal waveforms are some focus areas. Emphasis is put on the class of deterministic BSAR signals with wide bandwidth, such as short pulse signals, LFM signals, GPS and digital video broadcast terrestrial (DVB-T) signals, and low level of side lobes, such as Barker phase codes, complementary phase codes and GPS coarse/acquisition (C/A) and GPS precision (P) phase codes.

3.1. Short pulse waveform and the BSAR signal model

3.1.1. Short pulse waveform

Assume that the target is illuminated by a sequence of short monochromatic pulses, each of which is described by

[3.1]

where

In the above equation, A is the amplitude of the emitted signal; is the angular frequency; f is the carrier signal frequency; t = (m – 1)ΔT is the discrete current time, m = 1, 2, … is the number of current time samples, is the time duration of the signal sample, M is the full number of samples ...