National Aeronautics and Space Administration

Glenn Research Center

Reprogrammable, Space Qualified, Ka-band Software-Defined Radio for NASA Space Missions

FacebookLinkedInGoogle+PinterestMore

Since 1958 when NASA launched the first U.S. Earth satellite, Explorer 1, communications has been the life blood of non-terrestrial exploration. Radio communication is critical for both the safety of men and women in space (i.e., Apollo 13) and for the remote data collection/transmission of unmanned lunar, planetary, and deep space exploration crafts. Quite simply, more exploration means more data, and more data means higher transmission bandwidth and the need for higher reliability (and, by extension, higher transmission rates mean more data and more science). Now, advances in computer hardware, software, and integrating architectures will allow fixed-function, single-vendor, one-of-a-kind mission radios to be replaced with re-programmable Software-Defined Radios (SDRs).

NASA/Harris SDR

The NASA/Harris Ka-band implementation is the first with high-speed communications using SDR

NASA Glenn Research Center has advanced the state of the art by developing a reprogrammable, space-qualified, Ka-band SDR for NASA space missions. The innovation is a fully programmable, reconfigurable SDR operating in the Ka-band frequency range, qualified to provide exceptionally high data-rate communication and data transmission over multiple waveforms in a space platform. The radio was specified, designed, built, and programmed to be compliant with NASA’s common architecture for software-defined radios, known as the Space Telecommunications Radio System (STRS) standard.

NASA Glenn’s SDR is the first transceiver of its kind to operate in the Ka-band, enabling higher data rates than previously possible, which can help NASA exploit more science opportunities for investigation and analysis. The SDR also takes advantage of multiple innovations to enable on-orbit reprogramming once deployed, offering many advantages to future NAS missions, including the following:

  • Greater application portability and application development
  • Flexibility to adapt to new science opportunities while in orbit
  • Cost-, risk-, and schedule-savings benefits from reusing generic space platforms to meet specific mission requirements

This Ka-band SDR is the first reconfigurable space radio compliant with the NASA space network and Tracking and Data Relay Satellite System (TDRSS) communication satellites. This architecture provides commonality among NASA SDRs to develop, operate, and maintain space- and ground-based re-programmable assets. This technology also represents the first Ka-band SDR qualified for space applications, enabling higher data rates than previously possible. Most existing space radios have several previous generations behind them, and the designs are updated as required for specific mission requirements and as technology advances.

With this Ka-band SDR, future NASA space missions now have a space-qualified Ka-band radio platform with certified NASA TDRSS waveforms that can be leveraged for future missions, or modified as appropriate to meet future mission objectives. The existing waveform applications can be ported to future platforms, supporting the goal for waveform portability through the defined STRS application interfaces. The open STRS architecture creates an entirely new paradigm for total life cycle development and operation of space-based radios and transceivers.

The SDR offers extensive financial and technological benefits for near- and long-term NASA missions. For example, by providing the ability to change the radio’s operating characteristics through software once deployed to space, the SDR offers future missions the flexibility to adapt to new science opportunities, recover from anomalies within the science payload or communication system, and potentially reduce development cost, risk, and schedule by adapting generic space platforms to meet specific mission requirements.

The Ka-band SDR can be reconfigured to perform different functions or communicate with different stations without the need for multiple radios to accomplish each communication function. This technology effectively enables radio count reduction, thereby reducing mass and power resources, which helps to offset any increase brought about by adhering to a common architecture. The radio can be reprogrammed in orbit, thus allowing the addition of operational capability for new space or ground assets that were not available when the radio was launched into space.

NASA Glenn and Harris engineers collaborated extensively to develop this innovation, which included the Ka-band radio itself as well as the critical system testing and flight verification tests. The hardware and software architectures of this SDR enable development of different implementations based on the size and complexity of the mission and its specific requirements. The SDR is scheduled for inclusion in the Communications, Networking and Navigation Re-Configurable Testbed (CoNNeCT) payload that will launch in 2012 and be attached to the International Space Station (ISS) for future experimentation. The advancement of radio technology to be flown on ISS is a credit to the excellent team of NASA Glenn and Harris engineers and technicians participating in this venture, and it will allow NASA to better leverage its investments in radio technology by reusing the radio architecture across many future missions.

The NASA/Harris Ka-band implementation is the first with high-speed communications using SDR. Further reinforcing the beginning evolution to SDR, the Mars Reconnaissance Orbiter included an SDR UHF-based radio for inter-spacecraft communications. The team’s approach is pushing the evolution of megabit to mega-gigabit satellite telecommunications. Moreover, the self-error detecting and self-healing firmware technology demonstrated in this innovation is a pioneering implementation.

The potential opportunities that this technology opens for extended, autonomous operation are considerable.

Future NASA aerospace missions will benefit from the Ka-band SDR as a new paradigm of reconfigurable technology. For years, NASA has developed space-based communication radios that employed a fixed or static operation for an intended mission. Custom hardware circuitry provided limited flexibility both during development and while in orbit, creating a dependence upon the developer for communication signaling applications. Future radios can leverage the non-recurring costs to develop the first hardware platform, software, and waveform applications so that they will not have to be produced again, providing significant manufacturing cost savings.

Changes in mission planning or requirements would often lead to increased costs to NASA to redesign hardware circuitry to provide new functions. In addition, problems encountered during the space qualification process could only be repaired through hardware repairs or changes that resulted in significant cost and schedule overruns. The use of programmable electronics changes this situation, allowing new software to be used with the radio, even after deployment, saving significant life-cycle costs in the end.

Further economic benefits arise because the innovation makes radio capabilities more extensible to a variety of future applications. NASA Glenn is leveraging its investments in radio technology in other markets requiring communications such as emergency responders, firefighters, and wireless mobile networks. The hardware and software architectures of this SDR enable development of different implementations based on the size and complexity of the mission and its specific requirements. The architectures better allow the insertion of new technologies as hardware components become obsolete, thus making the innovation more extensible to a variety of future missions.

SDR technology specifically provides a solution to uneconomical and inefficient single-solution radio developments for each mission that have little reuse or extension across different missions. The SDR technology has vast military and commercial applications, most recently displayed by Harris’ recent award of the payload for the Department of Defense Operationally Responsive Space SARSAT program.

This accomplishment further emphasizes how open architectures and software-defined payloads are being embraced by programs to meet present and future mission requirements under tight budget and schedule constraints. Many near-Earth environmental missions will require Ka-band data communications. From sensing global change to providing real-time data and advanced warning for natural disasters (hurricanes, tornados, earthquakes, etc.), high bandwidth communications will enable a safer, more secure society.

POC: Gene Fujikawa, gene.fujikawa@nasa.gov, 216-433-3495