High temperature UHF SSVD™ oscillators and power amplifiers

The suitability of solid state vacuum device (SSVD^™) technology as applied to aerospace applications and transmitter systems at ultra-high frequency (UHF) or, in other words, up to 3 gigahertz (GHz) frequency transmitter systems operated at high temperatures will be reported. SSVD^™ is a vacuum electronics device based approach and technology that utilizes 3-d circuit design and advanced microfabrication methods including micro-electro-mechanical system (MEMS) technology to create highly integrated, high performance vacuum electronic devices that removes the material limitations on frequency and power capability compared to current solid state electronic devices especially at high temperatures. Solid State Power Amplifiers (SSPAs) including wide bandgap semiconductors suffer from mobility degradation and other detrimental effects whereas SSVD^™s are not affected by high temperatures. As a result, SSVD^™ is highly suitable for high temperature operation or, in other words, the transmitter system can handle high temperatures and heat with no degradation in operation. This high temperature capability ensures high efficiency and reliability of the transmitter system. It also reduces cooling requirements and, as a result, the size of the overall transmitter system. SSVD^™ technology can offer higher efficiency and longer life at high temperatures than solid state power amplifiers (SSPAs) which are currently employed at UHF frequency range. SSVD^™s can be designed to have cut off frequencies on the order of tens of GHz and, as a result, could easily be developed to support high power and/or efficiency at UHF frequencies. Based on the testing data obtained from a SSVD^™ operating at 500°C including before, during, and after 500°C operational third party testing, there was no degradation in performance during or after 500°C operation. High reverse breakdown voltages were also obtained at high temperatures from the SSVD^™ and the SSVD^™ also passes high radiation testing. Based on its construction method, the SSVD^™ power amplifier could be easily integrated into, for example; a heterodyne modulator for which amplification of the signal is required. The SSVD^™ voltage controlled oscillator and power amplifier were built into planar configurations and ready to be integrated with other active and passive components through a microstrip coupler to reduce system loss. Note that both the SSVD^™ voltage controlled oscillator and power amplifier were tested without significant increase in its noise level or operational frequency shift during high temperature operation. Based on the results we have obtained to date, solid state vacuum device (SSVD^™) technology is highly suitable to support high temperature operations of transmitter system for aerospace and other applications such as missions to the surface of Venus at including UHV transmitter systems.