Measurement and application of near-field scan data: Prediction of currents, radiated emissions, and probe characteristics

This dissertation examines the application of near field measurement techniques and analysis originally developed for the analysis of antennas to the specific case of electromagnetic compatibility.;The first section describes a procedure for estimating the current flowing in circuits and the chip lead frame from compensated near-field data. These techniques are applied to find currents on the pins of an integrated circuit, in traces buried beneath other traces in a PCB, and in traces over a slot in the ground plane. Methods of dealing with the ill-posed nature of the current-estimation problem are discussed, as are applications to electrically large structures.;The second section describes a procedure for using the equivalent current sources, derived from near field measurements, to represent the effects of EMI sources in enclosures and/or in proximity to other near field scattering objects. These methods will be applied to specific examples.;The third section describes and demonstrates a procedure, based on reciprocity, for characterizing (calibrating) near-field probes and compensating the near field probe measurements to reduce the near field distortion introduced by placing the probe in a previously unperturbed incident field. The effect of the near field probe in loading the source of the incident field will be neglected in all of the analysis in this section.;The last section of this work consists of an appendix summarizing the plane wave scattering theory and reciprocity theory previously developed by others and providing the underlying fundamental foundation for all of the proceeding sections.