Passive Aero-Acoustic Sensor Self Interference Cancellation. Phase 1

摘要

Some Army HMMWV armored personnel carrier vehicles carry air-acoustic sensorsystems comprised of a complement of roof-mounted microphones to detect and identify other vehicles and aircraft such as helicopters. The performance of these systems tends to become degraded as a result of the vehicle's own engine and road noise. Multi-channel noise cancellation, if correctly applied, is capable of removing most of the own-vehicle's engine self noise from the microphone outputs. The purpose of this project is to improve the performance of these acoustic systems through the application of multi-channel noise cancellation. The purpose of Phase I was to establish the efficacy of Signal Separation Technologies' SFR-SFC (signal-free Reference using Singular-value Decomposition) technique for performing multi-channel noise cancellation for the aero-acoustic sensor application. This efficacy has been firmly established as a result of Phase I tests and analysis. In a typical example, a signal peak previously submerged in noise of the same level was made to stand out over the noise by some 15 dB. The SFR-SVD technique to do multi-channel noise cancellation is covered by U.S. Patent No. 5,209,237 and foreign patents. It is available to the U.S. Government for Government purposes only on a royalty-free basis. For all other purposes, a license must be negotiated with Signal Separation Technologies. HMMWV Vehicle, Armored personnel carrier, Detection.