A compact channel patch antenna with reconfigurable circularly polarized pattern for mobile satellite communications
Lingxiao Xie, Lidong Chi, Bin Lin, Xianbin Wang, Yihong Qi
Abstract
A compact dual-band circularly polarized antenna with a characteristic of pattern reconfiguration is proposed for S-band satellite handsets. The antenna works as a patch antenna in a channel shape with no ground beneath reaching an overall size of 0.55λ × 0.14λ × 0.1λ. The dual-band performance is realized through multi-branch slots of the patch. The antenna mainly consists of a channel metal patch, a channel dielectric, and a simple feeding network. The overall shape of slot can be changed by the PIN diode on the patch to adjust the surface current direction, which in turn achieves 180° switching of the left-hand circularly polarized radiation beam direction. In addition, by combining the quadrifilar helical antenna, which is switchable in the end-fire beam direction, the designed antenna can realize the switching of four main beam directions to achieve 360° 3D spatial coverage. The proposed antenna is fabricated and measured to verify the proposed design. The test results show that the designed antenna obtains circularly polarized radiating characteristics in S-band with the center frequency of 1.98 GHz and 2.2 GHz, and the test results and simulation results are basically consistent, which indicates the superior performance of the designed antenna.