This research is divided into three major topics. The first topic, mechanical magnetic field generator for communication in the ULF range, is discussed in the first paper. The second topic, source reconstruction in near field scanning for RFI application, is discussed over the course of two papers. The third topic, analysis of imbalanced 2 or 3 Wire VHF LISN, is discussed in the last two papers.
In the first topic, the possibility to use a mechanical system (a rotating magnet) as a source (generator or antenna combined) of the ULF magnetic field is investigated. Ultralow frequency (ULF) communication systems have advantage over the RF systems in lossy media such as soil or water. A conventional way to create ULF fields is to use coils. It is demonstrated that the mechanical sources have advantage over coils in terms of occupied volume or dissipated power and can be a viable alternative for low-size, weight, and power applications. In the second topic, methods are presented to predict the high-frequency near electric- and magnetic- fields from a component using a Method of Moment (MoM) approach. Additionally, the impact of three major sources of error in near field scans: random measurement noise, cross field coupling, and position error, is investigated on field prediction. A clear decision-making process with examples is provided to guide the user toward selection of the best representation. In the third topic, an analysis of an imbalanced two- or three-wire VHF LISN is conducted in terms of its mode conversion and termination impedance. It is demonstrated that an imbalanced termination impedance provides a specified degree of conversion from differential- to common-mode, which can lead to more representative radiated emission test results --Abstract, page iv
