Target DOA Estimation Using Nonuniform Sparse Array for Low Frequency Radar

摘要

For low frequency radars operating at HF/VHF/UHF bands, normally a long uniform filled array is required to obtain accurate target azimuth DOA estimation and good spatial resolution. To reduce the hardware cost, the uniform filled array can be replaced by a nonuniform sparse array. However when conventional DOA estimation technique is used, the sidelobes of nonuniform sparse array will be very high and misestimation may occur. In this article some other DOA estimation techniques, including the classic MVDR algorithm, MUSIC algorithm, and a newly developed iterative adaptive approach (IAA), are investigated for nonuniform sparse array configurations. Their performances are extensively analysed and compared by both simulated and experimental data. The results prove that IAA can achieve good performance for nonuniform sparse array and is capable of resolving multiple targets with only one signal snapshot.