AN IMPROVED METHOD FOR RADIO FREQUENCY DIRECTION FINDING USING WIRELESS SENSOR NETWORKS

We present the design of a remotely deployable distributed wireless antenna system formed from wireless sensor network nodes. Specifically, the focus is on enhancing the detection range of a distributed wireless antenna system. The primary objective is to create a methodology to steer the beam in the desired direction to enhance radio frequency (RF) direction finding and follow-on signal reception. The distributed wireless antenna system uses a combination of time difference of arrival (TDOA) and adaptive beamforming to localize the target and enhance the reception in the target direction. The TDOA lines-of-bearing are calculated using a combination of the Cross-Ambiguity Function to calculate the actual time difference and the Newton-Raphson technique to focus the beamforming efforts. A Least Mean Squares (LMS) adaptive beamforming algorithm is then used to localize the target for further prosecution. Simulations indicate considerable improvement can be achieved using this combined method. I