Space Communications and Navigation Testbed (SCaN Testbed)

The SCaN Testbed is an experimental communication system that is located on the truss of the International Space Station (ISS). The technology has over 3000 hours of operations since launch in 2012, and is paving the way for infusion of SDRs and associated communications, navigation, and networking software applications into the SCaN integrated network. The project is led by the Glenn Research Center (GRC), and includes experiment activities by GRC, Jet Propulsion Laboratory, Goddard Space Flight Center, Johnson Space Center, industry, academia, and international space agencies.  Experimenters develop software for the Testbed's S- and Ka-Band radios and communicate through the Tracking and Data Relay Satellite System (TDRSS) or direct to a ground station. SCaN Testbed is the first NASA mission to support full-duplex space-to-space Ka-band communication, making it an ideal evaluation platform for missions considering the higher bandwidth and data rates that Ka-band can provide.

The SCaN Testbed is an experimental communication system that is located on the truss of the International Space Station (ISS). The SCaN Testbed has been infused into the SCaN Program, which is a part of NASA's Human Exploration and Operations Mission Directorate. The SCaN Testbed project has developed and enabled the infusion of multiple new software applications since launch that enhance the communications, navigation, and networking performance of the system. These applications are compliant with NASA's Space Telecommunications Radio System (STRS) architecture standard, which means they are easily portable to other STRS-compliant commercial radios.

New communications applications (waveforms) include a high-rate, bandwidth-efficient transmit waveform, capable of 1 Gbps data rate with NASA's low density parity check (LDPC) encoding. A Global Positioning System (GPS) waveform expanded the Testbed's capabilities to achieve the first in-space reception of the newest GPS frequency (L5-1176.45 MHz) and checkout of the Civilian Navigation Message (CNAV) data on behalf of the United States Air Force. Software developed for the avionics processor has not only enabled on-board routing among the three SDRs, but also enabled international interoperable disruption tolerant networking (DTN) tests with the French space agency, CNES. Currently, SCaN Testbed experimenters are implementing adaptive and cognitive radio applications that will improve operational efficiency, enhance data return, and mitigate the effects of interference on radio performance.

Understanding the development, verification, and operations of SDRs is critical to reduce risk and cost to future missions as SDRs emerge as the radio technology of the future. The International Space Station provides an ideal operations platform to verify SCaN Testbed technologies by enabling daily, on-orbit reconfiguration of the SDRs between existing and new software applications. The SCaN Testbed has advanced the technology readiness level (TRL) of SDRs from 4 to 8.

SCaN Testbed technologies earned three prestigious awards in 2013 including a Research & Development (R&D) 100 award for the first Ka-band transceiver, Wireless Innovation Forum Technology of the Year runner up for a breakthrough product or technology in the field of Software Defined or Cognitive Radio, and ISS Top Technology for Exploration.

Experimenters from around the Agency, small businesses, and universities create a broad base of SDR platform and application experts across the nation.  Working together, these experts will develop the communications systems of the future. SCaN Testbed continues to be recognized for the contributions it is making to enhance NASA's space communications capability.

SCaN Testbed was decommissioned in May 2019, following nearly 7 years of successful operations in space. The payload was removed from ISS on May 11, 2019 using the robotic arm and placed in the trunk of the SpaceX CRS-17 vehicle. The trunk and SCaN Testbed then burned up in Earth's atmosphere on June 3, 2019 during controlled re-entry.