Electromagnetic inversion of magnetic near-field data for device characterization

随着我们向物联网迈进，我们周围将出现无数的联网设备。这将显著增加为各种新的和现有的应用支持这种连接水平所需的天线（和电路）数量。为此，这些天线将需要适应许多不同的设备，其中许多设备可以接近人体，具有不同的物理结构，同时在不同的环境中提供各种远场和近场规格。为了缩短这些具有不同物理结构和辐射特性的许多天线（和电路）的设计和评估周期，需要可以提供增加的灵活性的电磁表征技术和算法，例如，在不同物理表面上的数据收集方案和诊断方面。与EMSCAN公司合作，拟议的研究项目调查了新的和/或改进的方法的开发，使用这些方法，我们可以以更灵活的方式进行天线，印刷电路板（PCB）和比吸收率（SAR）表征。这种灵活性可以是例如在数据收集方案、使用无相数据、合并先验信息或表征非规范表面方面。在这三个应用领域中的共同主题是，在所有这些应用中使用的数学公式，这是基于电磁反演框架，试图通过找到一些形式的电流进行表征。例如，这些电流可以是被测天线的等效电流，或者是SAR表征用体模中的感应对比源。为了让加拿大在物联网领域发挥主导作用，并从其市场价值中受益，在天线设计和测量领域，开发更灵活、更系统、更快速的天线设计和表征程序至关重要。拟议的项目旨在在定性方面为这一努力作出贡献。

As we move toward the Internet of Things, there will be a myriad of connected devices around us. This will significantly increase the number of antennas (and circuits) required to support this level of connectivity for various new and existing applications. To this end, these antennas will need to fit into many different devices, many of which can be close to the human body, with varying physical structure while providing various far-field and near-field specifications in different environments. To shorten the design and evaluation cycle of these many antennas (and circuits) with varying physical structures and radiation properties, electromagnetic characterization techniques and algorithms are needed that can offer increased flexibility, e.g., in terms of data collection schemes and diagnostics on different physical surfaces. In collaboration with EMSCAN Corporation, the proposed research project investigates the development of novel and/or improved approaches using which we can perform antenna, printed circuit board (PCB) and specific absorption rate (SAR) characterization in a more flexible manner. This flexibility can be for example in terms of data collection schemes, use of phaseless data, incorporation of prior information, or characterization on non-canonical surfaces. The common theme in these three application areas is that the utilized mathematical formulation in all of them, which is based on the electromagnetic inversion framework, attempts to perform characterization by finding some forms of currents. These currents can be, for example, the equivalent current of the antenna under test, or the induced contrast sources in phantoms for SAR characterization. For Canada to have a leading role in the Internet of Things and to benefit from its market value, it is important, within the area of antenna design and measurements, to develop more flexible, more systematic, and faster antenna design and characterization procedures. The proposed project aims to contribute to this endeavour within the characterization aspect.