A single fed wideband mode-reconfigurable OAMmetasurface CP antenna array with simple feeding scheme

摘要

In this paper, a low-profile mode reconfigurable orbital angular momentum(OAM) circular polarization (CP) array antenna is presented, which consists of2 × 2 elements and a single feed network. Each element is a metasurface subarraycomposed of 4 × 4 square patchs. The vias in the subarray produces 90phase difference between x- and y- polarizations, and CP is realized. Both the90 phase-shifting reconfigurable feed network and broadband 180 phase shiftby the mirror images are used to generate the OAM helical phase. The OAMmodes l can be dynamically switched between l = +1 and l = −1 by controllingoperation states of p-i-n diodes in the feed network. The CP and OAM impedancebandwidths are 13.3% (from 5.8 to 6.6 GHz). The peak gains for the twomodes are 9.4 dBi. The developed array antenna has the following advantagesof the least pin diode number, high gain, small size, lowest divergence angle,wideband CP, low cross-polarization and low fabrication cost. Therefore, theproposed antenna is very promising for modern high-speed and large capacitywireless communication systems.