Heron, Patrick Lascelles Modeling and Simulation of Coupling Structures for Quasi-Optical Systems. Under the direction of Michael B. Steer and James W. Mink Sponsored research was directed toward developing millimeter wave power sources utilizing quasi-optical techniques. A system consisting of an array of oscillators that radiated into a quasi-optical resonator was analyzed. Each oscillator was comprised of a solid state device and a radiating structure. A dyadic Green's function was developed for a Fabry-Perot resonator which consisted of a metallic planar reflector and a shallow spherical metallic reflector. The Green's function was applied to determine the driving point impedance matrix for an array of electrically small antennas within the resonator. An experimental X-band resonator was designed and fabricated, then one and two-port measurements were used to validate the theoretical calculations. A technique was determined for simulation of antennas that are not electrically ...

LUNSFORD II, PHILIP J. The Frequency Domain Behavioral Modeling and Simulation of Nonlinear Analog Circuits and Systems. (Under the direction of Michael B. Steer.) A new technique for the frequency-domain behavioral modeling and simulation of nonautonomous nonlinear analog subsystems is presented. This technique extracts values of the Volterra nonlinear transfer functions and stores these values in binary files. Using these files, the modeled substem can be simulated for an arbitrary periodic input expressed as a finite sum of sines and cosines. Furthermore, the extraction can be based on any circuit simulator that is capable of steady state simulation. Thus a large system can be divided into smaller subsystems, each of which is characterized by circuit level simulations or lab measurements. The total system can then be simulated using the subsystem characterization stored as tables in binary files.