With a minimal FTE investment and no additional procurement funds, the development of a low fidelity orbital GPS Signal simulator would is possible.
This IRAD leverages existing Navigator software, MATLAB simulation tools, Goddard Enhanced Onboard Navigation System (GEONS), and TDRSS Waveform and Noise Generator (TWANG). A small amount of work is required to integrate these existing products together to develop a GPS signal simulator.
The existing GEONS API interface will be used to provide the following information about the various GPS transmitting satellites: GPS satellite signals available, signal power estimates, signal delays, and signal frequencies.
An existing low-fidelity data bit generator will be leveraged that ingests GPS ephemeris/almanac data and produces the data bit stream that is generated by the GPS satellites. The software for the data bit generator is to be updated to conform more closely to the GPS data bit structure.
The GPS Satellite’s signal information (power, Doppler, and delay) and raw data bit message would be fed into either TWANG, or part of Navigator’s software would be repurposed for this application. Raw RF data would be output into a file, or onto a TCP socket. The recorded raw RF data would be replayed through our existing software receiver for initial testing.
Existing Universal Software Radio Peripherals (USRPs) in the lab would transmit the raw RF data to one of the Formation Flying Test Bed’s (FFTB) GPS receivers for testing, or into a separate USRP and then into the software receiver for hardware testing.More »
This would provide the following benefits:
The purpose of the Goddard Space Flight Center’s Internal Research and Development (IRAD) program is to support new technology development and to address scientific challenges. Each year, Principal Investigators (PIs) submit IRAD proposals and compete for funding for their development projects. Goddard’s IRAD program supports eight Lines of Business: Astrophysics; Communications and Navigation; Cross-Cutting Technology and Capabilities; Earth Science; Heliophysics; Planetary Science; Science Small Satellites Technology; and Suborbital Platforms and Range Services.
Task progress is evaluated twice a year at the Mid-term IRAD review and the end of the year. When the funding period has ended, the PIs compete again for IRAD funding or seek new sources of development and research funding or agree to external partnerships and collaborations. In some cases, when the development work has reached the appropriate Technology Readiness Level (TRL) level, the product is integrated into an actual NASA mission or used to support other government agencies. The technology may also be licensed out to the industry.
The completion of a project does not necessarily indicate that the development work has stopped. The work could potentially continue in the future as a follow-on IRAD; or used in collaboration or partnership with Academia, Industry and other Government Agencies.
If you are interested in partnering with NASA, see the TechPort Partnerships documentation available on the TechPort Help tab. http://techport.nasa.gov/help
|Organizations Performing Work||Role||Type||Location|
|Goddard Space Flight Center (GSFC)||Lead Organization||NASA Center||Greenbelt, MD|