Quantization degradation in superdirective processing of underwater acoustic arrays

The paper examines the effects of quantization in digital signal telemetry and processing of undersea acoustic signals. In particular, degradation in array gain is assessed for vertical line arrays that use superdirective beamforming. The background acoustic noise is modelled as broadband Gaussian noise having a spectrum and directionality typical of that measured in the deep ocean. Effects due to choice of number of bits, overload level and quantization scheme (uniform and µ-law) are examined over the entire frequency band of the received signals. The results agree qualitatively with those of earlier studies, but yield a better estimate of losses likely to be encountered in practice.