多通道微环光波束形成网络中载波处理的研究

Research on Carrier Processing in Multichannel Silicon Micro Ring Optical Beam Forming Network

基于相控阵雷达系统对大瞬时带宽和无波束偏斜的需求,研究了基于光学真延时的级联微环结构的多通道光波束形成网络的载波调制方案。级联微环结构的光学波束形成网络不仅瞬时带宽大、无波束偏斜,而且集成度高、延时量连续可调。通过理论推导和仿真分析,证明了在多通道微环光波束形成网络中,各通道的光在相干合成前必须进行载波抑制,否则不同通道的延时会相互干扰。采用的微环半径为20μm,硅波导损耗约为3 d B/cm,通过级联微环得到的延时带宽大于2 GHz,相位误差小于±10°。

Base on the requirement of large instantaneous bandwidth and none beam squint,carrier processing is studied in multichannel micro ring optical beam forming network. Optical beam forming network made of cascaded micro rings can not only meet the needs of large bandwidth and none beam squint,but also has unique advantages such as high integration degree and continuous adjustable delay time.Through theoretical derivation and simulation analysis,it is demonstrated that in such a system,carrier must be suppressed before coherent combining to avoid carrier induced inter channel interference.The micro ring radius used here is 20 μm and the waveguide loss is 3 dB/cm.The time delay bandwidth achieved is 2 GHz,with phase error less than ±10°.