A study of characteristics of underwater acoustic particle velocity channels measured by acoustic vector sensors

Abstract

Acoustic vector sensors measure orthogonal components of acoustic particle velocity. When used in underwater communication systems, they act as multichannel receivers. One advantage of a vector receiver, compared to an array of spatially-separated scalar receivers such as hydrophones, is its compact size. Some characteristics of particle velocity channels are studied theoretically or via simulations (A. Abdi and H. Guo, “Signal correlation modeling in acoustic vector sensor arrays,” IEEE Transactions on Signal Processing, vol. 57, pp. 892-903, 2009; H. Guo, et al., “Delay and Doppler spreads in underwater acoustic particle velocity channels,” J. Acoust. Soc. Am., vol. 129, pp. 2015-2025, 2011). In this paper, we use data measured by a vector sensor to study various key characteristics of underwater particle velocity channels, including delay spreads, signal-to-noise ratios, and possible correlations among different channels. By inspecting the eigen structure of channel matrices, we also investigate how various measured particle velocity channel impulse responses can affect the performance of an equalizer to detect transmitted symbols. The results are useful for designing proper vector sensor-based multichannel receivers in underwater communication systems. [This work was supported in part by the National Science Foundation (NSF), Grant IIP-1500123.]