K/Ka-Band Space-Flight Reprogrammable and Flexible Communications - Frontier Radio - Multi-Lingual

Future space-flight communications will need to cover wide frequency bands, have more computing power, be highly flexible, and be reprogrammable. The next-generation space-flight software-defined radio (SDR) developed for the NASA Space Communications and Navigation (SCaN) Polylingual Experimental Terminal (PExT) by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) provides these capabilities and more. This radio has completed flight qualification for use in the PExT demonstration. The radio receiver and transmitter cover the government / NASA, military, and commercial K/Ka-bands for relay and direct-to-earth communications. The radio supports Consultative Committee for Space Data Systems (CCSDS) compliant waveforms used in many NASA missions, and Digital Video Broadcast - Satellite - Second Generation (DVB-S2) waveforms typically used by commercial relay services. The field programmable gate array (FPGA) and embedded software are re-programmable in-flight so that entirely new waveforms can be uploaded in the future. In the flight demonstration, communications to NASA's Tracking and Data Relay Satellite System (TDRSS), Boeing / Inmarsat, and SES / O3b mPOWER will be confirmed. The PExT payload will be on a low earth orbit (LEO) spacecraft and has on-board Doppler compensation algorithms for both the forward and return links to relay satellites in various orbits. Optional AES-256 encryption is available for the forward link from the ground to the spacecraft. The radio uses an Ethernet connection to the spacecraft host computer. A powerful new feature is included that allows the user to connect to the radio over internet protocol after an RF link is established to a commercial relay provider; this provides access to a standard Linux operating system on the radio enabling future networking and on-board applications. The radio, along with the rest of the PExT payload, has completed integration and vibration testing at the spacecraft level for a scheduled rideshare launch in 2025. This paper focuses on the radio design, developments, and PExT flight test qualification. Future commercialization is planned with possible improvements including an even smaller form factor along with additional software applications, non-linear output predistortion, and future waveform support.