基于特征模理论的系统天线设计方法

激励出更多模式，造成隔离度变差。

图16、不同激励组合激发出不同的模式

从图16可以看出：当天线1工作，存在模式1和模式5，天线2工作时，存在模式2和模式5，但由于模式5的MS值很小，所以有很好的隔离度。

图17、不同馈电方式下MIMO性能比较

(CMA设计结果vs. 三种扫参优化得到的结果)

从图17可以看出：天线1，没有覆盖整个频段，但是天线2在整个频段匹配好，并且两个天线之间最好隔离度；具有最好的ECC 性能(<0.1) 和>0.5 dB 的MEG；天线1和天线2分别激励了不同的模式。

图18、CMA分析得到两种激励组合方式下的3D方向图

四、总结

本文简要介绍了特征模理论基础，并采用商业软件FEKO v14.0版本的CMA分析模块对几种简单的天线形式进行特征模分析，得到了丰富的模式特征参数，并展开分析，便于让大家清楚地了解CMA技术的应用。CMA方法广泛应用于天线设计，也同样应用于天线布局^[13][14]、电磁兼容以及目标隐身等领域。

作者：焦金龙，澳汰尔工程软件（上海）有限公司

参考文献

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