Wide-beam circularly polarized microstrip antenna with high front-to-back ratio for CNSS application

A novel circularly polarized (CP) microstrip antenna with wide beam and high front-to-back ratio is proposed for compass navigation satellite system (CNSS) application. Based on the single-fed patch antenna, parasitic strips are loaded on the same layer to broad the beamwidth. Reactive impedance structure (RIS) is designed as a reflector to obtain a high front-to-back ratio. More importantly, good circularly polarized performance can be obtained in a wider range of beamwidth by adjusting reflection phase. Experimental results show that the measured half-power (HP) beamwidth is approximately 147° and the 3dB axial-ratio (AR) beamwidth is more than 180°. A front-to-back ratio of 20 dB can be achieved within the bandwidth.