GPS Industry Examines Receiver Standards, as LightSquared Ponders Next Move

 - March 1, 2013, 12:55 AM

Since LightSquared’s bankruptcy last fall, a common perception was that the company had thrown in the towel and the GPS industry could cease looking over its shoulder, breathe a sigh of relief and get back to the navigation business. But that was not to be. In fact, what we have seen is more an extended time-out than a cessation of hostilities, as the combatants consolidated their positions. But neither has offered a cease-fire or surrender.

Each side has been sticking to its guns while modifying the most egregious target areas claimed by the other. The principal issue was that LightSquared sought to use two separate frequencies (called the upper and lower frequencies) to uplink and downlink Internet data between its current earth-orbiting satellite and its associated receiver system. The satellite signals would, like all satellite transmissions, be at very low power, but they would then be transmitted to terrestrial users via a nationwide network of high-powered ground stations. However, tests by the Federal Communications Commission (FCC) and other government agencies quickly showed that the ground-station transmissions, particularly at the upper frequency, created unacceptably severe interference with all types of GPS receiver at virtually all altitudes.

LightSquared acknowledged the interference, and offered two solutions. It would drop the use of the upper frequency that created the major interference, and it also introduced a receiver technique that minimized–but did not eliminate–the interference from the lower frequency. As a longer-term solution, LightSquared proposed that the FCC offer it a number of non-interfering frequencies in another part of the spectrum in a no-cost exchange for those which, LightSquared claimed, the FCC should never have encouraged LightSquared to use in the first place. However, this proposal is contentious within the telecommunications industry, where frequencies are routinely sold or auctioned for prices in the tens or hundreds of millions, and occasionally in the billions. A no-cost LightSquared frequency swap would have to be a political call, and it does not currently appear that the company has quite that much leverage.

The LightSquared faceoff inspired the GPS industry to examine GPS receiver technical standards, following suggestions from both industry and government officials after the interference tests that the lack of such standards could possibly have affected the test results, although not significantly. On the other hand, the GPS industry recognized a need to establish international receiver standards and a process to confirm their conformance, and this is now under way.

At the same time, while the future for nationwide, or worldwide, retransmission of broadband Internet is a desirable goal, its achievement through LightSquared is still unclear. If the company emerges later this year from its current bankruptcy, it will doubtless still wish to aim for that objective, though probably in a different form, well removed from the GPS spectrum. But as we have seen, having invested some billions of dollars in its LightSquared initiative, the company has shown itself to be a resourceful and innovative organization. In fact, Wall Street reports that investors have recently been buying the company’s debt, suggesting a degree of confidence in its return. Only time will tell.

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