Electromagnetic interference in electronic circuits and systems

This thesis examines the effects of electromagnetic interference (EMI) and coupling in circuits and systems. The coupling phenomenon is investigated in nonuniform transmission lines and adjacent via structures in microelectronic circuits. Radiation from metallic enclosures with apertures and lined with resistive materials is analyzed. Electromagnetic interference on a larger scale is studied in the Instrument Landing System receivers, where both in-band and out-of-band interference sources are considered. The method for modeling and analyzing vias in multilayered integrated circuits is based upon microwave network theory. The whole via structure, consisting of a vertical via passing through different layers and transitions from the microstrip lines or striplines to the vertical via, is divided into cascaded subnetworks. The parameters for each subnetwork are obtained from electromagnetic field analysis. The vertical via is modeled with equivalent magnetic frill arrays, and the transitions are characterized with the finite-difference time-domain (FD-TD) technique. For the electromagnetic coupling between two vias the evenand odd-mode approach is incorporated. Closedform expressions for the coupled noises on the passive via are derived. Results are presented both in the frequency domain and the time domain. Validation of the model has been carried out by measurements on a 4-layer structure. A method based on the wave transmission matrix to deal with nonuniform multiconductor transmission line systems is presented. The wave transmission matrix is employed to characterize the multiconductor transmission lines. The nonuniform