Hydrophone Arrays

Abstract

The goal of both passive and active sonar systems is reliable long- range detection and ranging capability, but the basic considerations that influence performance of the two types of sonar are quite different. The receiving array in passive systems such as towed arrays or wide aperture ranging arrays must be able to detect signals with unknown frequency content, and therefore must operate over a frequency band much greater than the band of a typical active system. And they must do so in the presence of interfering noise. Chap. 4 shows that there are many ways to design hydrophones with adequate broadband sensitivity that are small, lightweight, and inexpensive compared to the high-power projectors needed for active sonar. But the main problem in passive sonar is control of the interfering noise, especially in ship-mounted arrays.