A new method is developed to predict the scaling of the electromagnetic interference from a large system if similar subsystems are added. The method gives the predicted emission from multiple radiators as well as the level of certainty of the estimation. The proposed statistical approach is based on the phased array antenna theory and Monte Carlo simulation for a router with several line cards (N) and optical modules inserted. To validate the method, a large router with 498 optical modules with an unwanted radiation at 10.31 GHz was investigated in two different cases: the same frequency and different frequency per radiating subsystem. Several statistical experiments were performed for the proposed problem. The effect of phase and amplitude variations over the radiators is reported in this paper. The method is useful when it is not practical to assemble extraordinary amounts of identical hardware in a product installation. The results indicate the existence of a 10 log N (dB) tendency for the maximum electric field emission in a system radiating at the same frequency with random phase distribution over the radiators. For different frequency subsystems, the slope of the maximum electric field emission is lower than the 10 log N (dB) formula.

中文翻译：

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多个辐射器的 EMI 预测

如果添加类似的子系统，则开发了一种新方法来预测来自大型系统的电磁干扰的缩放比例。该方法给出了来自多个辐射器的预测发射以及估计的确定性水平。所提出的统计方法基于相控阵天线理论和蒙特卡罗模拟，适用于插入了多个线卡 (N) 和光模块的路由器。为了验证该方法，在两种不同情况下对具有 498 个光学模块的大型路由器进行了研究，该路由器具有 10.31 GHz 的无用辐射：每个辐射子系统具有相同的频率和不同的频率。对提出的问题进行了几次统计实验。本文报告了辐射器上相位和幅度变化的影响。当在产品安装中组装大量相同的硬件不切实际时，该方法很有用。结果表明，在以相同频率辐射且在辐射器上具有随机相位分布的系统中，最大电场发射存在 10 log N (dB) 趋势。对于不同频率子系统，最大电场发射的斜率低于 10 log N (dB) 公式。