Radar Systems Analysis and Design Using MATLAB, 3rd Edition

Chapter 5

Ambiguity Function - Analog Waveforms

5.1. Introduction

The radar ambiguity function represents the modulus of the matched filter output, and it describes the interference caused by the range and/or Doppler shift of a target when compared to a reference target of equal RCS. The ambiguity function evaluated at (τ,fd) = (0, 0) is equal to the matched filter output that is perfectly matched to the signal reflected from the target of interest. In other words, returns from the nominal target are located at the origin of the ambiguity function. Thus, the ambiguity function at nonzero τ and fd represents returns from some range and Doppler different from those for the nominal target.

The formula for the output of the matched filter was derived ...