Increased Power Handling of Vanadium Dioxide T/R Switches Using a Resonant Topology

The temperature- and power-dependent intermodulation distortion of a vanadium dioxide switch is investigated via a highly linear two-tone testbed at 3.5 GHz. OIP3 for this VO2 switch is extrapolated. RF-power-induced insulator-to-metal transitions (self-switching) are observed, as well as third-order intermodulation distortion reduction as the switch is driven further into the conducting state. A switch topology using VO2 switches to present either series or parallel LC resonances is investigated as a potential solution to the observed power handling deficiencies, and specifically investigated for transmit-receive duplexing applications. The possibility of a phase-change T/R switch employing reduced logic and exhibiting passive LNA protection against high-power interferers is considered using extracted linear models.