For those just tuning into the situation, here’s the snap-shot:
In one corner is a company called LightSquared, backed by Northern Minnesota rags-to-riches billionaire Phillip Falcone. In the other corner is the entire GPS industry. LightSquared is seeking to enter the nation-wide broadband market by installing 40,000 base stations that will relay LightSquared’s satellite-earth signal. The problem is the frequency range allocated to LightSquared by the Federal Communications Commission (FCC) is adjacent to the spectrum used by GPS, and tests have shown there are serious GPS interference issues. Consequently, the GPS industry and many user community heavy-hitters are more than a little upset. In its defense, LightSquared has claimed the interference issue is a GPS industry problem caused by commercial GPS companies manufacturing “sloppy” systems that have been using part of LightSquared’s spectrum for years. GPS manufacturers have responded by saying both LightSquared and the FCC are to blame. LightSquared because it fundamentally changed the design of its system by adding the 40,000 base stations after it was allocated the spectrum next to GPS, and the FCC because it granted LightSquared a conditional approval to proceed in January 2011 even though basic physics clearly indicated the LightSquared implementation plan would seriously degrade GPS.
After a 90-day period of testing mandated by the conditional approval confirmed interference was a major issue – LightSquared submitted a “new” plan in late June that critics claim has the same fundamental problem with physics – it won’t work without degrading GPS. Congress subsequently became interested in the situation and commenced a series of hearings in early September. On this past Friday, it turned politically ugly.
The crux of the matter is the testimony of four-star General William Shelton, the head of the Department of Defense’s U.S. Space Command. While some news organizations were telling a story focused on reports that Shelton had been asked by the White House to alter his testimony to be softer on the LightSquared proposal, others were saying the situation was a politically motivated attack on the President by a Republican controlled Congress.
From General Shelton’s testimony, here are some of the snippets of what’s got everybody in a huff:
- “…The innovative uses of GPS are also interwoven into a wide array of civil and commercial sector applications. Examples include the aviation community, where GPS is used by the Federal Aviation Administration (FAA) to help control our national airspace. GPS is used by the Department of Homeland Security for National border and maritime security. First responders, such as law enforcement, medical emergency and firefighting crews, depend on GPS for easy and accurate ground navigation allowing quick responses to time-urgent events. Activities such as mining, surveying, shipping, banking, and telecommunications rely on GPS’s PNT services as well. As a Nation, we have invested roughly $34 billion to field and operate the GPS constellation. Clearly, it has become a global utility serving a worldwide user population.
- As the Department of Defense’s experts on GPS, AFSPC participated in recent testing to determine the effects, if any, of the originally planned LightSquared broadband service on the continued availability and reliability of GPS…”
Now for some of the findings as reported by General Shelton:
- “..Based on the LSQ-provided deployment plan in urban areas, the typical user likely will be no more than 400 meters from a LSQ tower. The analysis showed that some GPS receivers could encounter signal reception interference at distances of several kilometers from a LSQ tower; therefore, the analysis concluded interference would be particularly acute in urban environments…
- “…Aviation receivers operating as far as 7.5 miles from LightSquared transmitters completely lost GPS and were degraded out to distances of more than 16.5 miles. For two representative receivers tested by the FAA, results also showed GPS would be completely unusable for an aircraft 500 feet above the ground in an area spanning Stafford, Virginia through Washington and Baltimore, and out to Frederick, Maryland.
- High precision GPS receivers such as those used for surveying and geological study requiring precise measurements were adversely affected out to 213 miles and totally lost GPS out to 4.8 miles.
- Based on testing performed at the Jet Propulsion Laboratory, a class of receivers used in space to conduct certain types of atmospheric measurements would be unusable up to 12% of the time while in their typical orbits.
- The State of New Mexico E-911 Program Director, who sent several GPS-equipped emergency and police vehicles to the test, stated in a letter to AFSPC that their equipment showed “the LightSquared network will cause interference to GPS signals and jeopardize 911 and public safety....”
- “…A conclusion in the LSQ recommendations paper is that interference “is because legacy GPS receivers do not adequately reject transmissions from base stations operating in the adjacent frequency band because the GPS receivers have been deliberately or, sometimes, inadvertently, designed or manufactured with the assumption that there would be no adjacent-band terrestrial transmissions.” In fact, GPS receivers were quite purposefully designed to operate in a portion of the radio frequency spectrum deliberately maintained as a “quiet neighborhood,” with neighboring frequencies primarily occupied by signals of comparable power levels, all based on the widely accepted understanding of previous FCC rules and intent. The proposed LightSquared transmitters will produce received signal strengths five billion times stronger than the GPS received signal…”
For the full testimony of General Shelton and others before the House Armed Services Committee on Thursday, September 15th, go here. That same day, the legal staff at LightSquared fired back at the Shelton testimony with a four-page rebuttal that you will find here.
Clearly, while there is a wide difference of opinion as to who is to blame for this situation – particularly since it has started to digress into political wrangling - one thing is certain. GPS as we know it is at risk. Indeed, this may be the single most important issue to come before the geospatial and/or emergency services communities in many years, yet many individuals seem to be either unaware or too lazy to even learn basic facts.
I would most strongly encourage you to not be one of those types on an issue this important to your respective community. In my opinion, the only way you can do that is by seeing political and related posturing for what it is, and instead focus your attention on the scientific facts as presented by experts. You can do that by reviewing information as found on the following sites:
- Armed Services Committee Testimony on LightSquared Interference Issue (as given September 15, 2011)
- Science Committee Testimony on LightSquared Interference Issue (as given September 8, 2011)
- FCC Filings (current)
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