Antenna array design for covariance-based direction-finding methods

Angle-of-arrival estimates based on the analysis of a spatial covariance matrix are particularly vulnerable to error in the presence of coherent signal interference. When this condition exists, the wave interference field is statistically nonstationary, and estimation techniques that are based upon an assumption of stationarity tend to produce poor results. A method is proposed for the design of antenna arrays that exploits the effects of time-averaging and spatial smoothing to approximate the condition of statistical stationarity and thereby enhance the performance of bearing estimation methods