光子学报, 2018, 47 (9): 0913001, 网络出版: 2018-09-15
基于爬坡算法的片上低栅瓣二维光学相控阵
Low Side Lobe On-chip Two Dimensional Optical Phased Array Based on the Hill Climbing Algorithm
硅光子学 相控阵 爬坡算法 光栅 栅瓣 干涉 Silicon photonics Phased array Hill climbing algorithm Gratings Side lobe Interference
摘要
通过两级定向耦合器结构实现了光学相控阵天线阵列的二维排布, 并设计了特殊C形弯曲波导进行热调作为阵元的相位控制器.提出一种针对阵元数量不高的稀布片上光学相控阵远场高阶干涉栅瓣的压缩方法.将均匀的阵元间距通过爬坡算法优化成非均匀间距, 以破坏栅瓣产生所需的干涉相长条件, 实现对栅瓣的压缩作用.在1 310 nm波长, 通过时域有限差分法对基于微型光栅耦合器天线的稀布阵列进行计算分析, 结果表明优化的阵元间距能实现-6~-7dB的栅瓣抑制比.
Abstract
A two-stage directional coupler structure is proposed to realize the two dimensional optical phased array, and a distinctive C-bend waveguide is designed for thermal regulation as optical phase shifter of array element. A method that compresses far field side lobes caused by high-order interference for sparse on-chip optical phased arrays is presented. Hill climbing algorithm is adopted to optimize the uniform antenna spacing and make it become non-uniform, which will greatly mitigate constructive interference conditions and then compress far field side lobes. Using finite-difference time-domain method to simulate the sparse optical grating coupler array designed at 1 310 nm wavelength showing that this optimization can realize a -6~-7 dB ratio of side lobe and main lobe.
杜书剑, 章羚璇, 王国玺, 李中宇, 张其浩, 谢鹏, 李燕, 米磊, 孙笑晨, 张文富. 基于爬坡算法的片上低栅瓣二维光学相控阵[J]. 光子学报, 2018, 47(9): 0913001. DU Shu-jian, ZHANG Ling-xuan, WANG Guo-xi, LI Zhong-yu, ZHANG Qi-hao, XIE Peng, LI Yan, MI Lei, SUN Xiao-chen, ZHANG Wen-fu. Low Side Lobe On-chip Two Dimensional Optical Phased Array Based on the Hill Climbing Algorithm[J]. ACTA PHOTONICA SINICA, 2018, 47(9): 0913001.