Abstract
The advantages of using optical fiber as a transmission medium for microwave signals have led to an increasing interest in the design and implementation of microwave photonic links. Advantages of optical fiber include; low loss, low weight, flexibility, immunity to Electro-magnetic interference (EMI), and the prospect of higher bandwidth. Using the properties of optical fiber; microwave photonic links can generate, distribute, and process microwave signals for applications such as radar, communications, and sensors. Despite its many advantages over traditional microwave links, microwave photonic links do still suffer from higher noise figure, poor dynamic range due to the nonlinear properties in the electrical-to-optical (E/O) and optical-to-electrical (O/E) conversion processes. This report presents a model and design of an efficient high-speed/high-linearity photodetector capable of meeting requirements imposed on the O/E conversion process by modern microwave and Electronic Warfare (EW) systems. The modeling and design effort will include the study of a backside illuminated Mesa structure Uni-Travelling-Carrier (UTC) Photodetector and a travelling wave UTC structure (TW-UTC). The Mesa structure design will target applications from L band to K band, whereas the TW-UTC structure will target W band applications. Both designs will include a novel approach to the semiconductor epitaxial layer structure to achieve the desired performance.