Other research topics in which I am interested include printed circuit antenna arrays, determination of semiconductor transport parameters by microwave methods, and microwave stripline and microstrip measurements and calculation techniques. The main thrust of my current work deals with the development of overmoded waveguide components and systems for use with new types of high-power microwave tubes, in particular the gyrotron. These tubes are being developed, in part, for use in plasma fusion reactors and deep space communications. In this program, we work on background theory, new design methods, computer simulation techniques, fabrication and fabrication methods, testing and development of testing techniques, as well as associated instrumentation and computerization problems.Gyrotrons are high-power high-efficiency microwave tubes which have been developed for frequencies from 8 to 150 GHz and above. Higher frequencies are continually being sought. The outputs of these gyrotrons are in unusual higher-order modes in large circular waveguides. Output modes such as the TE01, TE02, or TE03 are common. Rotating modes such as the TE15,2 or the TE22,2 are being used in higher frequency versions. These modes are not good for plasma heating or space communications. Thus mode converters are developed to change these modes the the TE11 or the completely linearly polarized HE11 mode in a corrugated waveguide. These converters sometimes take the form of periodic perturbation waveguide mode converters or mode transducing antennas such as the Vlasov antenna.The design of some of these mode converters involves working with sets of coupled-mode equations to find perturbation profiles for optimized performance. I am interested in a broad range of research areas. My work in these areas has included theoretical, experimental, computational, and instrumentation research at levels appropriate for both M.S. and Ph.D. projects.