结构参数对串联微环谐振腔编解码器性能的影响

光码分多址系统中, 光编解码器是影响系统性能的关键因素之一.自相关峰值旁瓣比(P/W)、自互相关峰值比(P/C)是衡量编解码器性能的两个重要指标.以硅基SOI微环谐振腔为载体, 提出了一种串联三环阵列的二维相干OCDMA编解码器模型.详细研究了耦合系数、损耗系数、阵列间距以及通道间隔对微环谐振腔编解码器性能的影响.结果表明, 半径为50 μm的微环, 环与直波导间耦合系数在0.6–0.7之间, 环与环间耦合系数在0.1–0.2之间, 损耗系数 < 2 dB/cm, 阵列间距大于3 mm, 通道间隔在25–36 GHz间时, 编解码器能够获得良好的性能.

Study of structure parameters effect on p erformance of optical en/deco der based on parallel-cascaded microring resonators

Optical en/decoder is one of the most crucial factors affecting the performance of the optical code division multiple access (OCDMA). The autocorrelation peak to maximum wing ratio (P/W) and cross-correlation ratio (P/C) are two important parameters to quantitatively evaluate the performance of the en/decoder.Based on the SOI parallel-cascaded coupled micro-ring reflector, a mathematical model of two-dimensional coherent optical en/decoder is established. Influences of the structure parameters including the coupling coefficient, the loss factor, the array distance, and the channel spacing on P/W and P/C ratios are discussed in detail. Results show that for the micro-ring with a radius of 50 μm, when the ring-bus and ring-ring coupling coefficients are 0.6–0.7 and 0.1–0.2, respectively, the propagation loss is lower than 2 dB/cm, the array distance is greater than 3 mm, and when the channel spacing is given between 25–36 GHz, the proposed structure can have an optimal performance of en/decoding.