SCaN Testbed Software Development and Lessons Learned

NASA Glenn Research Center, U.S.A., Denise.M.Varga@nasa.govNASA has developed an experimental flight payload, the Space Communication and Navigation (SCaN) Testbed, to investigate software defined radio (SDR) communications, networking, and navigation technologies, and is operational in the space environment. The payload consists of three software defined radios each compliant to NASA’s Space Telecommunications Radio System Architecture, a common architecture standard for space software defined radios. These software defined radios are new technology developments for NASA and industry partners. Launched in July 2012, the payload is externally mounted to the International Space Station truss for conducting experiments representative of future mission capability. Experiment operations will include in-flight reconfiguration of the SDR waveform functions and payload networking software. The flight system will communicate with NASA’s orbiting satellite relay network, the Tracking and Data Relay Satellite System (TDRSS) at both S-band and Ka-band and direct to the ground to any Earth-based compatible S-band ground station. The system will be available for experiments by industry, academia, and other government agencies to participate in the technology assessments and standards advancements. This paper focuses on software lessons learned through development, integration and testing as related to the avionics processor system, and the software required to command, control, monitor, and interact with the SDRs, as well as the other communication payload elements. I. INTRODUCTION HE National Aeronautics and Space Administration (NASA) Space Communications and Navigation (SCaN) Testbed Project is studying the development, testing, and operation of software defined radios (SDRs) and their associated applications for future use by NASA missions. To that end, the NASA Glenn Research Center (GRC) has assembled and launched a flight testbed which consists of reconfigurable and reprogrammable SDRs operating at L-band, S-band, and Ka-band, along with the required radio frequency (RF)/antenna systems necessary for communications. The three SDRs were built by Jet Propulsion Laboratory (JPL)/Cincinnati Electronics, General Dynamics Advanced Information Systems, and the Harris Corporation. The JPL SDR can receive Global Positioning Satellite (GPS) signals while simultaneously operating as an S-band transceiver, and is a heritage design based on the Electra software defined radio. The General Dynamics SDR is capable of full-duplex S-band communications, and leverages GD’s experience with the 4