The Space Telecommunication Radio System (STRS), an open architecture specification based on software-defined reconfigurable technologies, is being developed by NASA for future space-radio communications and navigation systems. This includes software-defined radios (SDRs), which offer advanced operational capabilities that will reduce mission life-cycle costs for space platforms. The objective of the open architecture is to provide a consistent, extensible environment on which to develop, manage, and operate the increasingly complex software radios used in NASA space missions. The open STRS architecture provides a framework for leveraging earlier efforts by reusing various architecture-compliant system components developed previously in NASA programs.
The U.S. Department of Defense (DoD) and industry spent a considerable amount of effort on the development of the Software Communications Architecture (SCA), an open architecture for next-generation military radio communication systems. The STRS architecture and the SCA share many goals; however, the constraints of space-based systems currently prevent full utilization of the SCA by NASA. The size, power, and mass of the system need to be minimized for the constrained space environment. Processors and other electronic devices used in space require radiation hardening. NASA radios generally operate at higher frequencies and higher data rate transmissions than the current SCA-compliant radios. Space SDRs also have to address concerns about added software complexity and its effect on system reliability. During NASA missions, access is generally limited to remote uploads to change the behavior of the radios.
To leverage the DoD work, the NASA Glenn Research Center prepared a report that examines aspects of the SCA that could facilitate the design and implementation of the STRS architecture. STRS compatibility with the SCA would allow NASA to utilize commercial development and testing tools, share waveform components, and reduce the programmatic costs of maintaining a separate architecture. Highly effective commercial software development tools are reducing the time and cost of developing SCA-compliant waveforms and platforms. STRS adoption of these commercial tools would provide a consistent set of standards and practices, possibly lowering the costs of platform and waveform development.
SCA application/hardware separation. CORBA, Common Object Request Broker Architecture.
Long description of figure 1.
STRS Application Software/Hardware Separation. POSIX, Portable Operating System Interface; API, application programming interface; HAL, Hardware Abstraction Layer.
There is commonality in a number of areas of the two architectures where NASA might be able to leverage assets derived from the SCA. However, the requirements and constraints associated with space-based systems prevent NASA from utilizing the current SCA specification, primarily because of the large footprint and resources, as well as the complexity due to the dynamic deployment capability of SCA waveform applications. For a NASA SDR architecture to be sustainable, it must accommodate the unique constraints and needs of the space environment. However, as technologies for the space environment evolve, they should allow the STRS architecture to incorporate more features and capabilities of the SCA.
Software Communications Architecture Specification. MSRC-5000SCA V2.2, Joint Tactical Radio System (JTRS) Joint Program Office, Nov. 17, 2001. http://sca.jpeojtrs.mil/
Quinn, Todd M.: Space Telecommunication Radio System: JTRS SCA Applicability to Space-Based Radios, Nov. 2005. Available from NASA Glenn Research Center’s Communications Technology Division.
Quinn, Todd; and Kacpura, Thomas: Strategic Adaptation of SCA for STRS. SDR Forum Technical Conference ‘06, session 4.2-01, Orlando, FL, Nov. 13-16, 2006.
Reinhart, Richard C.; Farrington, Allen; and Israel, Dave: Space Telecommunications Radio System STRS Open Architecture Description, Rev. 1.0, Space Operations Mission Directorate, Apr. 2006. Available from NASA Glenn Research Center’s Digital Communications Branch.
Reinhart, Richard C.; Farrington, Allen; and Israel, Dave: Space Telecommunications Radio System STRS Open Architecture Standard, Rev. 1.0, Space Operations Mission Directorate, Apr. 2006. Available from NASA Glenn Research Center’s Digital Communications Branch.
Find out more about the research of the Digital Communications Technology Branch: http://ctd.grc.nasa.gov/organization/branches/dcb/dcb.html
ZIN Technologies, Inc., contacts: Thomas J. Kacpura, 216-925-1266, Thomas.J.Kacpura@nasa.govLast updated: December 17, 2007
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