Acoustic Beamforming on Wireless Sensor Nodes

Abstract

Acoustic beamforming is described in general terms, and the problems of implementing online acoustic beamforming on a wireless sensor node are described. A low-power FPGA-based solution is presented, implemented on a sensor board for a MicaZ mote. An integrated FFT-based frequency filter is also presented. The results of tests performed in an anechoic chamber demonstrate that the system behaves as desired, performing beamforming in real time, filtering undesired frequencies, and transmitting the beamforms to another nearby node. Power consumption of the system remains within acceptable limits for wireless sensor deployment.