A Method to Widen the Range of Direction Finding by Time Modulated Array

This paper presents a method to enlarge the range of direction-finding in time modulated array. By improving the switching sequence, the distance between the harmonic main beams can be increased, and the direction-finding range is widened. In addition, a novel calibration method is proposed to improve the direction-finding accuracy when the incident direction reaches the main beam angle of harmonics. Simulation results verify the accuracy of the proposed method. In a seven-element time modulated linear array, the range of direction finding has been improved form ±59° to ±75°.