High frequency techniques at UHF and above

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"High Frequency Techniques at UHF and Above" broadly refers to techniques that can be used to mathematically describe electromagnetic waves at ultra-high frequencies in terms of rays. The proposed research will develop mathematical models that can be applied to practical problems described below. The aircraft industry is interested in low-profile "conformal antennas" that conform to the curved outer surface of the aircraft. Our recent research on "leaky waves" has led us to an understanding of what might happen to a leaky-wave antenna if the flat structure gets curved. We will explore the possibilities of designing curved leaky wave antennas. As a ray passes through a complicated bulding material such as reinforced concrete, it is difficult to predict its strength. We are developing a model for this situation. The results will be useful for the planning of indoor wireless networks. With support from the Department of National Defence, Ottawa we developed a computer code that uses high frequency techniques to predict the radar signature of naval vessels, aircraft, and other targets of interest. In the course of that work we have identified some theoretical limitations that need to be addressed. In particular, the effects of sharp corners and edges on a target are difficult to model, and this will require further basic research.