Proposal of Ultra-Short-Pulse Acoustic Imaging Using Complex-Valued Spatio-temporal Neural-Network Null-Steering

We propose complex-valued spatio-temporal neural-network null- steering for wideband acoustic imaging with ultra-short pulses. We combine a complex-valued neural network (CVNN) and power-inversion adaptive array (PIAA) scheme to realize a practical-resolution imaging in the azimuth direction (direction perpendicular to the range direction) even with a small-aperture array. Simulations suggest that the proposed method presents a higher resolution than conventional methods such as Capon’s method as well as a real-valued neural-network PIAA method.

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