U.S. Defense, Transportation Say Keep Wireless Comm Away from L-Band

July 9, 2011  - By
Image: GPS World

The U.S. Departments of Defense and Transportation declared their strong opposition to the proposal of LightSquared Subsidiary LLC to operate a nationwide broadband service within the spectrum immediately adjacent to GPS signals, in a letter sent on June 14 to the National Telecommunications and Information Administration (NTIA). The agencies acted on behalf of the on behalf of the National Executive Committee for Space-Based Positioning, Navigation, and Timing, which they are responsible for co-chairing.

The Departments asked the NTIA administrator to advise the Federal Communications Commission (FCC) to continue to withhold authorization for LightSquared to commence commercial service per its proposed deployment of a terrestrial service within the 1525-1559 MHz bands. LightSquared’s proposal is to deploy a network of 40,000 base stations along with some satellite coverage over 139 major markets in the United States.

According to their official statement, “The Departments continue to support the National Broadband Plan, but cannot do so at the expense of a global, ubiquitous utility such as the Global Positioning System. The Departments encourage further assessment of any alternative spectrum and/or signal configuration plans.”

The DoD/DoT letter was sent just prior to the original deadline for the final report of the Technical Working Group commissioned by the FCC to research and recommend on this matter. Certainly, the respective signers were cognizant of the contents of that report, at least on the test results regarding interference with GPS. As it turned out, on June 15 LightSquared asked for more time, and was granted a two-week extension. The final report was filed with the FCC on June 30.

The Departments’ position followed an interagency review of the findings of the National Space-Based Positioning, Navigation, and Timing Systems Engineering Forum (NPEF),  tasked to assess the GPS impacts of LightSquared’s deployment plan as originally filed. The NPEF determined that, if permitted to operate as originally planned, LightSquared’s signals would significantly interfere with GPS users and, as a result, impact national security, economic security, and public safety nationwide. The NPEF report served as working material for the TWG report.

The NTIA Administrator forwarded the letter and report to the FCC Chairman on July 6. These materials can be found at www.PNT.gov.