Performance of a cylindrical hydrophone array for practical use

Cylindrical arrays are widely used in sonar systems for underwater target detection. For the sake of reducing calculation, each line of hydrophones at the same azimuth direction aligned with the cylinder axis are hardwired together in practice and thus, each line array with omnidirectional sensors becomes a directional sensor steered to broadside. As a result, the cylindrical array can be treated as a circular array with directional elements. In this paper, a model is introduced for computing the array gain and the white noise gain of an acoustically transparent cylindrical array. The three-dimensional acoustic field is described by the angular spectral density function and the steering vectors are represented by the cylindrical harmonic expansions, based on the derived noise cross-spectral matrix. Simulation results of array gains and white noise gains with the conventional beamformer (CBF) and the minimum variance distortionless response (MVDR) beamformer for different situations are presented, which has a guiding significance for practical applications.