Direction Finding Based on Time-Modulated Array With Multiharmonic Analysis

Direction finding with time-modulated array (TMA) has attracted considerable attention recently. In this communication, a multiharmonic analysis for direction finding based on TMA is proposed. The linear regression model of the two-element direction-finding system is established, and its noise covariance matrix is also analyzed. With the best linear unbiased estimator (BLUE), the high-order harmonic components which were previously ignored in the estimation can be effectively utilized to improve the direction-finding accuracy. Compared with conventional single harmonic analysis, simulation results are provided to demonstrate validation of the proposed method for improving the direction-finding accuracy. An experimental system based on two-element TMA is constructed and implemented to verify the feasibility of the proposed method.