Acoustic Vector-Sensor FFH "Blind" Beamforming & Geolocation

An acoustic direction-finding and blind interference rejection algorithm for up to three noncooperative wideband, fast frequency-hop (FFH) spread spectrum signals of unknown hop sequences and unknown arrival angles is presented. This algorithm avoids the need to adjust beamforming weights to accommodate frequency variations in the frequency-hopping signals. This approach deploys one acoustic vector-sensor (a.k.a. vector-hydrophone), which is composed of two or three spatially collocated, but orthogonally oriented, acoustic velocity-sensors plus an optional collocated pressure-sensor. The spatial collocation of all component sensors comprising such an acoustic vector-sensor frees the beamforming weights of any dependence on the signals' hopping frequencies.