Description: Chronos Technology, proposes to deliver a comprehensive, and conceptually validated feasibility study (in Phase I) for a novel compact, rugged, stable, low power, radiation hardened +500 degrees C radio frequency modulator (HTMX). The modulator would be a subsection of a transmitter used in extreme high temperature and rad-hard space applications such as in-situ atmospheric and surface explorations in the high-temperature high-pressure environment at the Venusian surface (485C, 95 atmospheres). Our intent is to complete the phase 1 study and deliver a design roadmap to the implementation and fabrication of the design in Phase 2. The proposed modulator feasibility study would also address the packaging aspect of the HTMX, its miniaturization and manufacturing processes and guidelines to facilitate reliable and repeatable device fabrication and its full adaptation to mission deployment. Our proposed solution offers compelling features such as a rugged package that would withstand atmospheric pressure in excess of 95 bar ambient pressure at +500 degrees C. The design and analysis of the HTMX configuration would include frequency scalable output, and commercially available compact package footprints. Since any hot planet lander system requires reliable communication, the frequency tolerance for HTMX will be optimized to enable reliable transmission fidelity for the Venusians in-situ surface exploration. The underlying objective in evaluating the different modulation schemes is to keep the approach simple. keeping it simple will positively impact the reliability and the eventual TRL of the proposed solution. Considering the harsh operating environment and the limited operating life for the system, we focus on a simple and reliable frequency modulation scheme. Our approach will also enable very efficient adaptation of the design to ASK (amplitude shift key) modulation as well.HTMX in itself would include other side benefit of a reliable and stable rad-hard clock source.

Benefits: The topic of the proposal reflects the focus on the NASA missions to Venus and other hot planets. Given the high temperature nature of the work proposed, there could be other derivative outcomes from the same technology. There is potential to configure the GaN transistors used in PWM circuits. There are PWM circuits being planned to be used in power processing units (PPU) as part of space based electronic thrusters. The high temperature capable PWM could be positioned very close to the power switches without the need for large and heavy heat sink. Doing so will result in more efficient DC-DC boost convertors.

The non-NASA applications could potentially extend to more than one type of application and maps to multiple market segments. High temperature GaN transistor and varactor diode will always have applications in the harsh industrial, nuclear reactor, jet engine control and energy exploration. Varactor diode by itself has potential applications in system synchronization for networked down-hole monitoring systems. The same approach could be used for seismic sensors. High bandwidth of the GaN transistors could potentially be used in simple clock source designs for commercial space