Design of Low RCS Circularly Polarized Patch Antenna Array for BeiDou Navigation Satellite System Applications

This paper presents a low scattering, circularly polarized (CP) patch antenna array designed for BeiDou navigation satellite system (BDS) operation at B3 (1268.52 ± 10 MHz) band. The out-of-band radar cross section reduction (RCS) is achieved by utilizing a coding artificial magnetic conductor (AMC) ground. The AMC ground is designed by placing artificial magnetic conductor (AMC) unit cells together to achieve a phase difference between 180±37°. The out-of-band RCS is reduced more than 10 dB from 6.5 GHz to 10.5 GHz, corresponding to a relative bandwidth of 47 %, with a maximum reduction of 26 dB at 8.6 GHz. The corner truncation technique is employed to obtain circular polarization. Simulated results related to transmission and, reflection coefficients, axial ratio (AR), and RCS reduction of the proposed antenna array are presented. The performance of the proposed BDS array is validated.