通信机箱内连接器电磁干扰建模与仿真

Modeling and analysis of electromagnetic interference from connectors in communication chassis

随着工作频率的提高,通信系统面临的电磁干扰问题日益严重。其中高速连接器信号走线上的高频电流是产生电磁辐射的主要干扰源。对含有复杂元器件的通信机箱进行电磁建模与仿真长期面临结构过于复杂、仿真与测试难以匹配等困难。提出基于机箱Q值测算融合的方法建立等效仿真模型,基于区域分解对干扰源和机箱进行协同仿真,并采用有源叠加实现随机信号叠加效应的仿真分析。提出的分析方法可准确模拟真实机箱的谐振及耗散特性,简化连接器多端口激励随机叠加效应的仿真计算,实现机箱泄漏场强的准确预估。

With the increase of working frequency, electromagnetic interferences （EMI） become more and more serious for electronic equipment. High-speed connectors are the main interference sources. Numerical simulation of EMI/EMC for complicat- ed communication system still suffers from many challenges such as too many complicated details, wideband frequency response, and inconsistency with real testing. In this paper, a simplified simulation model is proposed firstly with the aid of measurement and theory of reverberation. Then, a cooperative simulation is achieved through domain decomposition method （DDM）. Furthermore, a superposition method is adopted to investigate the random effect brought by the uncertainty of transmission signals. The resonance and loss characteristics of chassis can be modeled exactly by the proposed method. Besides, the analysis of random effect is simplified. Consequently, the leakage field through the chassis is accurately predicted.