Sonar Systems and the Sonar Equation

Abstract

The purpose of this chapter is to introduce several basic concepts related to sonar systems and their analysis through the sonar equation. The components of a sonar system are described, including monostatic, bistatic, and distributed systems. Examples of how they can be used to localize objects of interest are presented for active and passive systems. The Doppler effect, arising from motion of the sonar platform and/or the object of interest is described as well as how it affects standard sonar pulses. The sonar equation, which is a performance evaluation of a sonar system in terms of the signal-to-noise power ratio (SNR), is introduced for passive and active systems. The SNR required to achieve a desired detection or estimation performance (known as the detection threshold term in the sonar equation) is described for common signal models, detection algorithms, and for angle estimation with a line array of sensors.