实时波前处理机中的同步开关噪声抑制

Study on suppression of simultaneous switching noise in the real-time wavefront processor

为解决自适应光学实时波前处理机中同步开关噪声问题，本文针对波前处理机电路特点，结合三维全波及电路仿真，对板上电源同步开关噪声来源进行了分析，并研究了去耦电容、分割电源平面及蘑菇型电磁带隙结构对噪声的综合抑制作用。研究结果表明，通过良好的器件布局、合理地进行电源平面分割及在关键器件周围加入去耦电容可降低平面间噪声，蘑菇型电磁带隙结构带宽高截止频率低的特性，具有良好的同步开关噪声抑制作用。针对实时波前处理机进行了仿真，采用系统级和板级噪声抑制措施后，在0～4 GHz 频带内噪声隔离度达到-52 dB ，满足处理机的电源完整性要求。

In order to reduce the simultaneous switching noise（ SSN ） in the Adaptive Optics（ AO ） Real-Time Wavefront Processor（ RT-WFP） ,in accordance with the feature of RT -WFP , 3-D full wave and circuit simulation methods are applied to analyze the board-level SSN . By researching decoupling capacitors , the split power plane , the electromagnetic band gap（ EBG） structure for noise suppression , the results show that through a well device layout , reasonable power plane split and place decoupling capacitors around the key components can reduce the plane noise , and that mushroom-like EBG structures have a high bandwidth and low cut-off frequency characteristics with a good SSN inhibition effect . Finally , applying system and board-level noise inhibition measures to RT-WFP , a suppression of SSN from 0GHz to 4 GHz is achieved with a high mitigation level of - 52 dB , the power integrity requirements of RT-WFP are met .