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Long-range detection in acoustic sensor networks

The performance of various localisation schemes in sensor networks can be improved by long-range detection. However, its performance deteriorates under noisy environmental conditions. This work presents a system implementation of an acoustic ranging mechanism based on wideband ultrasonic linear chirps and time-reversal technique to counter the negative influence of channel multipath. We investigated the performance of our technique through experimentation with chirps of length 500 milliseconds. The proposed scheme provided distance ranging up to 10 meters, and showed an improvement in peak detection with respect to conventional techniques.