Self-Biased Radiation Hardened Ka-Band Circulators for Size, Weight and Power Restricted Long Range Space Applications

Ferrite control components including circulators and isolators are fundamental building blocks of Transmit/Receive modules (TRM) utilized in high data rate active space transceivers and transponders for both long-range (LR) and low earth orbit (LEO) systems. These components are utilized to protect high power amplifiers (HPA) during the transmit cycle from destabilizing, and potentially harmful, power reflections from the antenna element. During receive cycle these components are utilized to direct lower power received signals with minimal attenuation to the low noise amplifiers (LNA). As such, performance specifications of these ferrite control components, such as bandwidth, insertion loss, isolation, power handling, temperature stability, radiation hardness, and linearity impose strict limitations on the overall system performance. Over the course of the proposed Ph1 SBIR program self-biased ferrite control components based on highly textured hexagonal ferrite compacts which have the potential to eliminate biasing magnets and significantly reduce the size, cost, and weight of the TRM while concurrently increasing power handling capability, and improving temperature stability and radiation hardness will be investigated. Specifically, a research and development path to realizing high performance self-biased ferrite materials and device designs for operation in space based environments at Ka-band (>27 GHz, 31.5 - 34 GHz targeted) is outlined.