Four-access, 80 mm aperture all phase-controlled liquid crystal laser antenna
Zhiqing Liang, Yanwei Huang, Xiaoxian He, Wen Dongmei, Yingli Wang, Xiangru Wang
Abstract
High speed, wide range, and high precise beam steering technology are fundamental to free-space optical communication (FSO). Liquid crystal optical phased array (LC-OPA) is capable of achieving non-mechanical beam steering. This paper demonstrates a parallel, four-communication access beam deflection antenna based on LC-OPA, providing a large aperture, wide steering range, and high pointing precision. This antenna is composed of a coarse tracking subsystem using cascaded liquid crystal polarized grating (LCPG) and a fine tracking subsystem based on LC-OPA. The optical aperture is 80 mm × 80 mm, arranged in 2 × 2 subapertures, each serving a single wavelength beam. Besides, a cascaded control platform based on field programmable gate array is proposed to realize low-latency response. This optical antenna achieves a steering resolution of 20 μrad and covers a range of ±12 deg in two dimensions, laying the foundation for simultaneous access of multiple terminals in FSO communication network.