Jamming mitigation by randomized bandwidth hopping

We present bandwidth hopping spread spectrum (BHSS), a novel technique to improve the jamming resistance of wireless communications. In BHSS, the bandwidth of a signal is hopped rapidly in a manner that is unpredictable to the jammer. We show in this work that by combining bandwidth hopping at the transmitter with adaptive filtering at the receiver, BHSS is able to improve the jamming resistance of the communication beyond the processing gain of conventional spread spectrum techniques such as DSSS and FHSS without an increase in RF spectrum requirements. We have designed and implemented a BHSS transmitter and receiver system on off-the-shelf software-defined radios. Our experimental results with different hopping patterns show that BHSS is able to boost the power advantage of spread spectrum communication by 8 to 20 dB for jammers of fixed bandwidth. When both transmitter and jammer hop randomly, the average power advantage we achieve with our system is 11.4 dB.