Characterising electromagnetic fields of integrated electronic systems in enclosures - a ray-wave approach

电子消费品和支持互联网的智能基础设施需要高度集成的微型电子系统。这种小型化的主要问题之一是，不同组件之间可能会出现不必要的相互作用。根据电子元件内电流的变化率，这些元件辐射电磁波，电磁波可以耦合到结构的其他部分，并可能造成干扰。控制电子设备中的电磁干扰正成为一项日益重要的挑战。数字时钟速度正在不断提高，高性能系统中的数字时钟速度已经超过10 GHz，预计到2020年将达到20 GHz。这是在高度敏感的无线电频率范围内，模拟模块和芯片大小的组件成为高效的辐射器和接收器。此外，增加电路密度和降低电源电压将导致抗扰度降低。因此，未来集成电子系统的设计过程将必须包括比目前更详细的电磁兼容性(EMC)表征。以快速高效的方式对设备中复杂的多信号组件进行EMC研究将极大地简化行业中的设计决策，并有助于降低成本。在高频下提供快速可靠的EMC建模工具的挑战是巨大的；在复杂的多源环境和GHz范围内确定包括多次反射、绕射和干扰在内的电磁场已经是一项艰巨的任务。对于现实的电子设备，潜在的源场还取决于(先验未知的)操作模式，因此是非周期性的和时间相关的；它们的作用方式与随机的、不相关的输入信号相似。事实上，目前还不存在EMC方法来对源自去相关的噪声源的电子设备内外的瞬时信号进行建模。这项提议旨在通过开发一种有效的数值方法和伴随的测量技术来正面应对这一挑战，以便对多功能电子设备内外的辐射瞬时电磁场进行建模。新的数值方法基于波动混沌理论的思想，采用Wigner-Weyl变换和相空间传播技术。它利用了波相关函数与相空间密度之间的联系。项目组成员最近开发了有效传播这些密度的方法。这样，我们就可以直接根据统计度量进行工作，例如适用于随机场的平均值和场关联函数。这种创新的方法需要从测量中输入数据，这需要重新考虑标准测量技术。特别是，电子部件的相关双探头近场测量变得必要，这些测量将作为项目的一部分进行开发和测试。提出的解决EMC问题的方法是全新的，而且之所以成为可能，是因为诺丁汉大学数学科学和电气工程方面的独特专业知识组合，这两个行业合作伙伴inuTech和计算机模拟技术(CST)提供的支持在整个过程中都将是至关重要的。这种新的思维方式将为EMC研究提供必要的飞跃，以满足电子行业的需求；它将增强现有EMC协议的适用性，并提供应对未来挑战的工具。

Electronic consumer goods and internet-enabled smart infrastructures require highly integrated miniature electronic systems. One of the main problem with this miniaturisation is that unwanted interactions can arise between different components. Depending on the rate of change of currents within electronic components, these components radiate electromagnetic (EM) waves which can couple into other parts of the structure and can cause interferences. Controlling electromagnetic interferences within electronic devices is becoming an increasingly important challenge. Digital clock speeds are relentlessly increasing already exceeding 10 GHz in high-performance systems and expected to reach 20 GHz by 2020. This is within range of highly sensitive radio frequencies where analogue blocks and chip-sized components become efficient radiators and receivers. In addition, increasing circuit density and decreasing voltage supplies will result in decreased immunity levels. Future design processes of integrated electronic systems will therefore have to include a much more detailed electromagnetic compatibility (EMC) characterisation than is done at present. Carrying out EMC studies for complex multi-signal components within a device in a fast and efficient way will simplify design decisions in industry enormously and will help to bring down costs. The challenges of delivering fast and reliable EMC modelling tools at high frequencies are enormous; determining EM fields in a complex multi-source environment and in the GHz range including multiple-reflections, diffraction and interferences is a hard task already. For realistic electronic devices, the underlying source fields depend in addition on the (a-priori unknown) mode of operation and are thus aperiodic and time dependent; they act in many ways like stochastic, uncorrelated input signals. Indeed, no EMC methodology for modelling transient signals inside and outside of electronic devices originating from decorrelated, noisy sources exists today. This proposal sets out to meet this challenge head-on by developing an efficient numerical method and accompanying measurement techniques for the modelling of radiated transient EM fields inside and outside of multifunction electronic devices. The new numerical method is based on ideas from wave chaos theory using Wigner-Weyl transformation and phase-space propagation techniques. It makes use of the connections between wave correlation functions and phase space densities. Methods for efficiently propagating these densities have been developed recently by members of the project team. In this way, we can work directly in terms of statistical measures such as averages and field correlation functions appropriate for stochastic fields. This innovative approach demands input data from measurements which require a rethink of standard measurement techniques. In particular, correlated two-probe near-field measurements of electronic components become necessary which will be developed and tested as part of the project. The proposed way of approaching EMC issues is completely new and becomes possible only due to the unique mix of expertise available at the University of Nottingham both from the Mathematical Sciences and the Electrical Engineering side Support provided by two industrial partners, inuTech and Computer Simulation Technology (CST), will be vital throughout. This fresh way of thinking will provide the necessary leap within EMC research to satisfy the demands of the electronics industry; it will enhance the applicability of existing EMC protocols and provide the tools to meet the challenges of the future.