Raster-scanned wave-digital filter architectures for multi-beam 2D IIR broadband beamforming

Abstract

Two-dimensional (2D) beam filters find applications in highly-selective directional enhancement of spatio-temporal (ST) plane-waves (PWs). A 2D raster-scanned (RS) wave-digital filter (WDF) hardware architecture, using a uniform linear array (ULA) of sensors, based on a 2D LR-ladder prototype network is proposed for obtaining M independently-steerable broadband beams having adjustable selectivity. FPGA-based prototypes for 2,3 beams supporting upto 32 broadband sensors are as well as measured results, FPGA resource consumptions, and maximum speeds at various fixed-point precisions, are provided. On-chip verification of the M-beam 2D IIR beam WDF architecture leads to multi-beamforming in applications such as directional audio, multimedia, seismic, and ultrasonic signal processing.