A fast, efficient approach to implementing SRDF techniques

Superresolution direction finding (SRDF) involves estimating the directions of arrival of multiple signals, generally utilising a multi-channel receiver and a suitable antenna array. A principal advantage of SRDF techniques is their ability to resolve two or more signals impinging on the array when their angular separation is less than the its natural beamwidth. This paper has addressed the efficient implementation of weighted spectrum type SRDF techniques. It has been shown that the Newton-Raphson root-finding technique can be applied to this problem. Moreover, when applied to weighted spectrum type methods, it provides a fast, accurate, computationally efficient peak-finding approach. This has been validated using both simulated data and real data collected in the HF band.