LightSquared and GPS

Sep 2011 | No Comment

The controversy around LightSquared and GPS has nicely been summarized at We are reproducing it for the benefit of our readers

What is LightSquared?

LightSquared Subsidiary LLC is a company that plans to provide a wholesale, nationwide 4G-LTE wireless broadband network integrated with satellite coverage.

LightSquared will combine existing mobile satellite communications services (formerly known as SkyTerra) with a ground-based wireless communications network that uses the same L-band radio spectrum as the satellites.

On January 26, 2011, the Federal Communications Commission (FCC) issued an Order and Authorization giving LightSquared conditional approval to build out its ground-based wireless network (referred to as an ancillary terrestrial component, ATC) by reusing its authorized mobile satellite service (MSS) spectrum. The approval is subject to further testing and FCC review (see below).

Why is the GPS community concerned?

The base stations of the LightSquared network will transmit signals in a radio band immediately adjacent to the GPS frequencies. The GPS community is concerned because testing has shown that LightSquared’s ground-based transmissions overpower the relatively weak GPS signal from space. Although LightSquared will operate in its own radio band, that band is so close to the GPS signals that most GPS devices pick up the stronger LightSquared signal and become overloaded or jammed.

There is also concern that the FCC may approve a technical solution to the problem that requires millions of existing GPS users to upgrade or replace their devices.

What is being done to address the concerns?

In its Order and Authorization, the FCC required that LightSquared create a working group with the GPS community “to address interference concerns regarding GPS and, further, that this [working group] process must be completed to the Commission’s satisfaction before LightSquared commences offering commercial service.” LightSquared committed $20 million to the working group and worked closely with the U.S. GPS Industry Council and other participants to complete interference testing.

The FCC ordered LightSquared to file monthly progress reports and a final report due June 15, 2011. On June 15, LightSquared requested and the FCC approved an extension of the deadline to July 1, 2011. They submitted their final report on June 30, 2011, along with a separate document providing their recommendation to the FCC. The FCC opened a 30-day public comment period on the report and recommendations, with a comment deadline of July 30, 2011.

LightSquared cannot commence commercial operations of its terrestrial network until the FCC, “after consultation with NTIA [National Telecommunications and Information Administration], concludes that harmful interference concerns have been resolved and sends a letter to LightSquared stating that the process is complete.”

Independent of the FCC-ordered study, the government’s National Space-Based PNT Systems Engineering Forum (NPEF) conducted its own testing of the potential interference to military and civilian GPS users from LightSquared’s terrestrial network. The NPEF completed its report on June 1, 2011; the unclassified public version was released July 6, 2011.

What is the Executive Branch position on this issue?

The government GPS community is working closely with LightSquared and the U.S. spectrum regulators to ensure that GPS users are protected from interference and unnecessary re-equipage. The U.S. Government continues to support the President’s National Broadband Plan and facilitate its implementation consistent with the preservation of national and economic security.

Federal agencies have conducted extensive technical studies to understand the interference effects and seek potential mitigations. Their initial analysis is complete and was provided to the FCC through the National Telecommunications and Information Administration (NTIA). The results clearly demonstrate that implementing LightSquared’s planned deployment for terrestrial operations poses a significant potential for harmful interference to GPS services.

Prior to the FCC Order and Authorization of January 2011, the National Coordination Office and multiple federal agencies expressed concern about potential GPS interference from LightSquared. On behalf of the Executive Branch, NTIA sent a letter to the FCC stating that the LightSquared proposal raised “significant interference concerns that warrant full evaluation” to ensure that federal agencies’ use of GPS is not adversely impacted.

On July 6, 2011, the NTIA Administrator sent another letter to the FCC stating that, based on the government testing and analysis, his earlier concerns about GPS interference remain unresolved. He recommended that the FCC continue to withhold authorization for LightSquared to commence commercial operations. NTIA, in coordination with federal agencies, is still reviewing the LightSquared working group test results and will continue to consult with the FCC.


“Analysis carried out in Europe . . . has shown that transmission from LightSquared base-stations do indeed have considerable potential to cause harmful interference to [our] receivers operating in the United States.” – European Commission

“[W]e would first like to confirm the information of the LightSquared system service deployment plan in Hawaii and Guam area to determine whether the impact to our monitoring stations would present.” – Japan Aerospace Exploration Agency

“Without the ability to quickly, efficiently, and often in real-time, provide through GPS the accurate geospatial information private and government consumers have come to expect, not only will the costs to provide such data skyrocket, but also much of that data will be obsolete before it can be made available for its intended purpose.” – American Congress on Surveying and Mapping & The National Society of Professional Surveyors

“[The TWG’s] results greatly concern AEM as our member companies have invested billions of dollars on the research and development of equipment products dependent on an uninterrupted GPS signal. . . . The results of the TWG’s extensive study clearly demonstrate allowing LightSquared to move forward is reckless and doing so places GPS based equipment at certain risk.” – Association of Equipment Manufacturers

“[T]he waiver granted LightSquared to deploy and operate a terrestrial network using frequencies adjacent to GPS [should] be withdrawn until sufficient testing and evaluation has been conducted with adequate assurances that precision based GPS will not be adversely impacted.” – American Association of State Highway and Transportation Officials.

“LightSquared has utterly failed to take seriously the safety of America’s aviation system, and the Commission cannot similarly engage in denial and ignore the serious threats to public safety posed by LightSquared.” – Aircraft Owners and Pilots Association & General Aviation Manufacturers Association

“LightSquared completely ignores the fact that high precision GPS is embedded in equipment in extensive use in the aviation sector and that Low 10 MHz interference to such precision GPS will jeopardize an important part of air safety for the American flying public.” – Deere & Company

“The bottom line is that LightSquared has been afforded an extraordinary opportunity to make the case that its proposed use of the MSS band is viable without causing harm and cost to government and private industry in excess of the benefits of its proposal. . . . The condition set forth in the Commission’s January 2011 order – that harmful interference to GPS must be resolved – has not been satisfied, and LightSquared cannot be allowed to commence operations.” – Trimble Navigation Limited

“[N]o mechanism exists that would enable LightSquared to mitigate the harmful interference revealed by the testing program. . . The Commission, through proper procedures, should reject LightSquared’s Recommendation, rescind the conditional waiver, and otherwise ensure that the conclusions reached from the work of the TWG and further studies/tests be codified in its rules governing ATC use in the L-band.” – Lockheed Martin Corporation

My Coordinates
His Coordinates
Anthony J Russo, Ed Norse
Mark your calendar
September 2011 TO August 2012

1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)

Leave your response!

Add your comment below, or trackback from your own site. You can also subscribe to these comments via RSS.

Be nice. Keep it clean. Stay on topic. No spam.