An industry-level implementation of a compact microwave diode switch matrix for flexible input multiplexing if a geo-stationary satellite payload

We have developed a electronically reconfigurable 4×4 switch matrix for satellite communications at Ka-band downlink frequencies (17 ... 22 GHz), utilizing low-temperature co-fired ceramic multilayer technology. During a successful one-year on-orbit verification aboard a German test satellite, the switch matrix showed continuous reliable operation and achieved the technology-readiness level (TRL = 9) for low-earth orbit missions. Based on these promising results und underlying qualification capabilities, we have designed an advanced version of the switch matrix as part of a flexible input multiplexer for operation during the entire operational lifetime of the German geo-stationary Heinrich-Hertz mission. The challenge of this approach lies in the combination of latest research concepts with an industry-level space-qualified microwave system-in-package approach including an automated hybrid assembly process, following the highest standards for satellite payload systems. Beside introducing and verifying new technologies in orbit, and thus reducing the design cycles for future satellite payloads in general, increased reproducibility and reliability of the module, and reduced manufacturing costs are further important consequences. The switch matrix incorporates double-sided hybrid integration, hermetic sealing of bare-die components, space-qualified PIN-diode switch-ICs, and wire-bonded coaxial connectors.