Abstract
Acoustic Spiral-Wave Active Localization is a low-complexity technique for determining location of acoustic targets (see Dzikowicz et. al. 2019, JASA 146, 4821-4830), which relies on the phase difference between reference and spiral wavefront(s). The phase between the returned reference and spiral wavefronts directly encodes the target’s bearing from the transmitter. Receivers can be standard omnidirectional hydrophones, as the phase difference is intrinsic in the methods used to generate the waves and completely independent of the receiver. This Spiral-Wave Active Localization technique allows comparatively small aperture receivers to resolve target bearing and range as an alternative to larger beam-steering receiver arrays, reducing hardware costs, signal processing requirements, and physical size of embedded Active Sonar Localization systems. This research presents a monostatic model of spiral detection and tracking for multiple targets in sparse noise limited environments. Trade-offs of different pulse compression waveforms and signal processing techniques applied to Spiral-Wave Active Localization will be evaluated. Simulation and experimental results from an acoustic spiral wave beacon in an underwater test tank will be presented. Results show good agreement to resolve targets in horizontal and vertical planes with a compact aperture.