Advanced RF Microwave Devices
The Advanced Devices Group has the primary objective of investigating fundamental technological and materials advances and their application to Communications Technologies.
Thin and thick films of the thallium-based HTS are deposited on a variety of substrates, with and without buffer layers, in collaboration with the Department of Materials. Microwave characterisation of these films is carried out, over the frequency range 1-40 GHz, by cavity end wall replacement, parallel plate, dielectric resonator and confocal resonator techniques. Devices such as delay lines, antennae, free space mixers, filters, resonators and an integrated hybrid voltage controlled oscillator have all been successfully operated at 77K and demonstrated to have performance superior to similar devices implemented in copper or silver. Work is continuing on the development of disc resonators and filters, and hybrid circuits and sub-systems for microwave communications. Applications include digital signal processing and CDMA spread spectrum systems. The engineering of a system/cryocooler package is investigated in collaboration with the Cryogenics Group.
The Advanced Devices Group activities of the Communications Group, the Materials Department and the Cryogenics Group (all at Oxford University).