Outdoor experiment results for tracking airborne high-speed broadband acoustic sources
William Garth Frazier, Chad Williams, Jay E. Williams, Kenneth E. Gilbert · The Journal of the Acoustical Society of America · 2002
Recent results of tracking airborne high-speed (subsonic) broadband acoustic sources with an experimental system are presented. The system consists of three acoustic arrays, wireless telemetry systems, real-time signal processing and tracking processors, and a tactical operation center-style display unit. The acoustic signal processor consists of a coherence-based detector and generalized cross correlator. The real-time tracking processor uses a modified extended Kalman filter algorithm. In this particular work, the calculation of acoustic sensor-to-source-bearing information will be briefly discussed along with the operation of the source detector, which is adaptive and dependent upon both amplitude and signal coherence. Special emphasis will be placed on how the tracking algorithm is compensated to accommodate unknown and variable data latencies produced by acoustic signals propagating from distant sources that are moving at a significant fraction of the speed of sound. Experimental results include estimates of source position, speed, and heading versus time. Estimates of source state uncertainty and comparison to truth data are also provided. [Work supported by the U.S. Army Space and Missile Defense Command.]