基于5 μm厚向列相液晶的高效圆极化相控阵系统的设计、校准和实验验证  

High-Efficiency Circularly Polarized Phased Array Based on 5μm-Thick Nematic Liquid Crystals:Design,Over-The-Air Calibration,and Experimental Validation

作　　者：Xin Yu Wu Fengshuo Wan Hongyuan Feng Shichao Jin Chong Guo Yu Wei Dunge Liu Yuqian Yang Longzhu Cai Zhi Hao Jiang Wei Hong 

机构地区：[1]State Key Laboratory of Millimeter Waves,School ofInformation Science and Engineering, Southeast University,Nanjing 210096,China [2]State Key Laboratory of Space-Ground Integrated Information Technology,Beijing Institute of Satellite Information Engineering Beijing 100095,China [3]Research Institute of Millimeter-Wave and Terahertz Technology(RIMMATT),Nanjing 211111,China

出　　处：《Engineering》2024年第1期69-81,共13页工程（英文）

基　　金：supported in part by the National Natural Science Foundation of China(NSFC;62122019 and 62293492);the National Key Research and Development Program of China(2019YFB2204704);the Fundamental Research Funds for the Central Universities;the Zhishan Scholar Program of Southeast University(2242022R40038).

摘　　要：This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquidcrystal-based phased array(LCPA),including the design,over-the-air(OTA)in-array calibration,and experimental validation.The LCPA contains 16 phase-shifting radiating channels,each consisting of a circularly polarized stacked patch antenna and a liquid-crystal-based phase shifter(LCPS)based on a loaded differential line structure.Thanks to its slow-wave properties,the LCPS exhibits a maximum phase-shifting range of more than 360°with a figure of merit of 78.3(°)·dB^(-1)based on a liquid crystal layer with a thickness of only 5μm.Furthermore,an automatic OTA calibration based on a state ergodic method is proposed,which enables the extraction of the phase-voltage curve of every individual LCPA channel.The proposed LCPA is manufactured and characterized with a total profile of only 1.76 mm,experimentally demonstrating a scanned circularly polarized beam from-40°to+40°with a measured peak gain of 12.5 dBic and a scanning loss of less than 2.5 dB.The bandwidth of the LCPA,which satisfies the require-ments of port reflection(|S_(11)|)<-15 dB,an axial ratio(AR)<3 dB,beam squinting<3°,and a gain variation<2.2 dB,spans from 25.5 to 26.0 GHz.The total efficiency is about 34%,which represents a new state of the art.The use of the demonstrated low-profile LCPA to support circularly polarized scanning beams,along with the systematic design and calibration methodology,holds potential promise for a variety of millimeter-wave applications.

关 键 词：Circularly polarized Liquid crystal Liquid-crystal based phased array(LCPA) Phase shifter Over-the-air(OTA)calibration 

分 类 号：TN8[电子电信—信息与通信工程]