This dissertation presents new concepts in front-end design for radio receivers with large, multiband tuning ranges.
This dissertation presents new concepts in front-end design for radio receivers with large, multiband tuning ranges, which are required to support large bandwidths over very large tuning ranges, and antennas that are usually narrowband or that support multiple narrow bandwidths. The author describes an improved use of multiplexers to integrate antennas and receivers compared to traditional techniques, which are limited in their ability to handle simultaneous channels distributed over very large tuning ranges but are important for frequency-agile cognitive radio, surveillance, and other wideband or multiband monitoring applications. The dissertation presents the goal of achieving sensitivity and how to improve the bandwidth to the maximum possible consistent with that goal, it then discusses the procedure which was developed for designing antenna-multiplexer-preamplifier assemblies. The author demonstrates that this approach can significantly increase the usable bandwidth and number of bands that can be supported by a single, traditional antenna, verified through field experiments.