Lightsquared: A Hardware Solution

LightSquared says it has a hardware solution that mitigates its interference issues with high-precision GPS services. Each receiver will cost between $50-$300, depending on device and specs, the company said.

The satellite phone company has offered to spend “tens of millions” of dollars to retrofit GPS devices with their proprietary component, in hopes of convincing the government to approve a billion-dollar plan to launch an independent 4G LTE network.

LightSquared is building a nationwide 4G LTE wireless broadband network using spectrum adjacent to GPS. Many in the GPS industry say the service would interfere with their devices since terrestrial towers would overpower weak GPS signals from satellites.

Javad GNSS has completed designing and testing prototypes that can be adapted to work with existing high-precision GPS devices, including those already being used in the field. LightSquared said it can be on the market by November and developed their device with Javad GNSS to eliminate interfere with precision GPS devices.

Javad Ashjaee, president and CEO of JAVAD GNSS, gives two reasons why high-precision receivers are more affected by the LightSquared signal:

  • The crucial importance of the arrival time of the signal edges; the edges are first to be distorted by interference. Narrow filters, proposed as a solution by LightSquared, also blur the signal-edge shape.
  • The encryption of P-code on L1 and L2 bands, degrading their effectiveness by a factor of 1,000, according to Ashjaee. “Encryption does not do any good to anybody.”

Ashjaee says Lightsquared should stay further away from the GPS signal, and use a cascade of filters; secondly, he calls on President Obama to discontinue P-code encryption, at least until the new L2 signal is operable in 8 or 10 years. “This would make GPS less vulnerable to the LightSquared project and others like it.”

P-code encrypts the GPS signal. GPS World and Inside GNSS have more on the issue.

“The U.S. policy of national security and P-code is 30 years old,” said Ashjaee. “Since the inception of GPS, there is no shred of evidence that GPS has ever been used to attack any U.S. national security, let alone its P-code signals,” said Ashjaee. Russia has its own GLONASS with un-encrypted P-codes.

The Coalition to Save Our GPS was unconvinced:

“LightSquared has, as usual, oversimplified and greatly overstated the significance of the claims of a single vendor to have ‘solved’ the interference issue. There have been many vendor claims that have not proven out in rigorous tests and the demanding tests of marketplace acceptance. Moreover, this is not a one-size-fits-all situation and a few prototypes does not a solution make. The estimated 750,000 to 1 million high-precision GPS receivers now in use in the United States vary widely: there are hundreds of different high-precision devices used in performing thousands of different tasks. High-precision GPS supports a wide variety of uses, including agriculture, construction, aviation, surveying and many scientific and safety-of-life applications.


Satellite navigation allows small electronic receivers to determine their location (longitude, latitude, and altitude) to within a few metres. The United States Global Positioning System (GPS) is still the only fully operational GNSS, but others are close to fully operational. They include:

Satellite consultant Tim Farrar says, “Despite, Mr Falcone’s attempts yesterday to dismiss the January 2011 FCC waiver as ‘irrelevant’ to the question of GPS interference, it seems very likely to become a central feature in the Congressional investigations that the House Oversight Committee is now initiating.

Rep. Darrell Issa (R-Calif.) said Tuesday that his committee plans to investigate government loan programs to private corporations in light of allegations of improper dealings between the White House and failed energy company Solyndra and wireless start-up LightSquared.

Related GPS articles on Dailywireless includes; More Testing for Lightsquared, Lightsquared: Another Plan, Lightsquared & Sprint Announce Sharing Agreement, Lightsquared Files Official FCC Report , Lightsquared: Plan “B”, Lightsquared: Lawmakers Skeptical, Lightsquared + Sprint Deal Done?, Lightsquared Gets 2-week Extension, Ergen Likely Got TerreStar, Charlie Ergen’s Spectacular Triple Play, Lightsquared Interference: No Immediate Fix?, LightSquared: GPS Interference Found, Lightsquared: Plan B from Outer Space?, Harbinger: 59MHz or What?. Time Warner Cable + Lightstream?, Lightsquared Signs Cricket Wireless, Another Rumor: Lightsquared + Sprint?, Lightsquared + Sprint?, Charlie’s Big Play, LTE Spectrum: It’s War, Lightsquared: What GPS Interference?, Harbinger Sells Inmarsat Shares, FCC Green Lights Lightsquared, LightSquared: In Trouble?, Lightsquared Unfurled

Posted by Sam Churchill on .

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