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LightSquared Sessions at Survey Summit: A Possible Solution? Print E-mail
Written by Marc Cheves, LS   
Monday, 11 July 2011

During the plenary session at the Survey Summit, Jeff Carlisle (a LightSquared VP) and Peter Large (representing the Save our GPS Coalition) each presented their case. Carlisle stated repeatedly that LS started the process ten years ago, and that all interested parties—including the GPS manufacturers—were well-aware and signed off. Legally, he is correct, but it seems to me that the answer to the question Why didn't anybody object? is quite simple: nobody knew the impact until the tests actually began. Prior to that, the system only existed on paper.

Carlisle made a convincing case: LightSquared has already invested $4 billion and plans to invest a total of $14 billion. There will only four providers of 4G broadband in the U.S. (AT&T, Verizon, Clearwire and LightSquared) and our country, with only 60% penetration with wireless, ranks 17th in the world. He emphasized that LS has expressed a willingness to alter its plans to avoid interfering with GPS.

Large said that the Coalition's largest concern is that even though LS is saying that it will roll-out by using the lower of its two authorized bands, it still has legal authorization to use the band closest to GPS, the band that—based on recent tests—completely obliterates precision GPS.

Much has been made of LS's contention that its system will not impact 99.5% of users. The trouble with this is that precision users—surveying and mapping, construction and agriculture—fall within the 0.5%. Furthermore, studies have shown that this half a percent generates the largest amount of economic benefit to our country. And as Gavin Schrock has pointed out, it would be shame if the U.S.—the country that gave the free GPS to the world—is the only country that will not be able to use precise GPS if LS is allowed to proceed with all of its authorized frequencies.

At an LS panel presentation yesterday, Javad Ashjaee shocked the audience by saying, "We love LightSquared!" After the chatter subsided, he said that communication is as much a part of GNSS as positioning is. He painted a picture where, by adding a GPS board, the LS transmitters could become a 40,000-base station RTN, and indeed, RTNs all over the world could use this approach.

But the most shocking of Javad's comments was a call for the U.S. military to discontinue the encryption of the P-Code on L2. If we look back in time, Ronald Reagan, after the Russians shot down the Korean airliner, instructed the military to make GPS available to the world. But it wasn't until President Clinton issued his Presidential Decision Directive that instructed the military to turn off Selective Availability that the use of GPS began to explode.

Javad's position is that P-Code encryption does not provide any security benefits to our country. And indeed, since the military gained theater control—the ability to affect the signals being broadcast from a single satellite—I agree with Javad that the military has what it needs to achieve its mission with GPS, with or without P-Code encryption.

After the meeting, I spoke with Javad and learned that unencrypting the P-Code will not result in more power for that signal, but instead will make it easier to find, and ultimately lower the cost of receivers because the manufacturers will not have to employ so many engineering tricks to utilize that signal. He likened it to a mesh being placed in front of a light bulb: the light still comes through, but if the mesh is removed, the light comes through more clearly. Javad said, "The current encryption of the P-Code has caused the P-Code signals to be 1,000 times less effective and more vulnerable to all interferences in general and to LightSquared in particular."

In his usual inimitable way, Javad has produced a video that lays out his two-fold solution: not using the upper of the two bands that LightSquared is authorized to use, and unencrypting the P-Code. In addition, the video gives an easy-to-understand explanation of the signals, how they work, and why unencryption will help. You can watch this short video HERE.

Without a doubt, broadband is something we need, and both sides agree on this. I heard anecdotal statements that 4G makes 3G look like dial-up. When there's not very many people sharing it, speeds as high as 30Mb/sec have been achieved. And even with a lot of people sharing the bandwidth, speeds of 3-5Mb/sec are common. LightSquared is concerned that its thus far $4B investment is at risk. The precise community, with its giant contribution to our economy, is also critical. We need to find a way to coexist and compliment each other. As Javad, said, "This is an engineering problem, not a legal problem," and added, "It should be called the Coalition to Save GPS and LightSquared, and the answer is staring us right in the face."

 
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