LightSquared GPS Testing: Spirent’s Perspective
The FCC, LightSquared and GPS industry have all agreed that the many questions around the potential for LightSquared’s proposed L-Band terrestrial/satellite network to cause interference with GPS can only be answered with accurate and thorough testing.
As mandated by the FCC, LightSquared and the United States Global Positioning System Industry Council (USGIC) have established a GPS Technical Working Group (TWG) to investigate the issues surrounding potential interference.
Spirent has been active in providing test equipment to help with the investigation and in contributing test plan automation to ensure that results are available in time to meet the TWG deadlines. Test equipment provided includes GPS simulators and, for testing in the “cellular” category, Spirent is supplying its complete, automated GPS/A-GPS test solutions. Spirent is a supplier of the test equipment and automation; the actual test execution, results analysis and reporting is carried out by the organisations appointed by the TWG.
If the test data shows that GPS and A-GPS performance metrics are indeed degraded by terrestrial L-Band signals in any particular part of the overall cellular receiver test plan, Spirent solutions will be able to precisely determine the severity and likely impact, helping to provide the industry and the FCC with the data needed to obtain a clear picture of how GPS and the L-Band terrestrial signals from LightSquared’s network will coexist in the real world.
Spirent’s position is neutral on the question of whether interference, or the risk of interference, will indeed be an issue. Spirent’s role has been to provide test systems and test automation expertise to enable quantification and analysis of the likely impact in a wide range of scenarios.
For more information on the testing required, please refer to the following web site: http://www.pnt.gov/interference/lightsquared/. For advice on systems capable of testing interference effects on GNSS please contact email@example.com.