Multi-Band Power Source for ITER Reflectometry

The technical requirements for the ITER LFS Reflectometer include a frequency range from 50 ¿ 170 GHz, a source power level of 150mW or more, and a frequency sweeping time of ten microseconds or less. Further, the various frequencies must be coupled simultaneously into a single circular waveguide, so that the reflectometer probes the same volume of the plasma with all frequencies and within the required sweep time. This project will demonstrate an all-solid-state source that achieves all of the above technical requirements. The approach is to break the frequency range into five frequency bands and use a combination of fundamental mode waveguide diplexers and a fundamental-to-multimode triplexer to couple the power from the five sources into a single circular waveguide. Commercial Applications and other Benefits as described by the awardeeIn addition to fusion applications, the high-power frequency-agile source should find use in radio-astronomy, chemical spectroscopy, atmospheric studies, plasma diagnostics, short range and secure communications, the detection of chemical and biological threats, and imaging systems. The application to imaging systems is particularly promising because terahertz waves, like microwaves, are able to penetrate a wide range of materials while maintaining a useful level of image resolution.