LightSquared accuses government of ‘rigged’ interference tests LightSquared has issued a public protest over the results of GPS interference testing by the US government of its planned LTE mobile network, claiming the tests have been “rigged” to fail. Last week EXCOM released the results in a letter to the US Commerce Department, and they were about as unequivocal as it gets. The …
I am not surprised by either aspect, that the tests show significant problems with a large range of current GPS, or that LightSquared would cry 'foul' and argue it was all biased against them.
I have always sided with the GPS case because (A) there is so much in use that it has become the de-facto standard for interference rejection, and (B) that LightSquared got the band on the cheap knowing it was not licensed for ground-based networks by the FCC, then lobbied for a change.
Sadly the dumbest ones are the FCC who even considered such a plan without proper engineering analysis, but both the GPS manufacturers who made the littlest attempt at protection and LightSquared who acted as the bully in trying the get the change-of-use through, they both have a share of dumbness to reflect upon.
"but both the GPS manufacturers who made the littlest attempt at protection and LightSquared who acted as the bully in trying the get the change-of-use through, they both have a share of dumbness to reflect upon."
The basic fundamentals of GPS signals below the noise floor, right next to ground based Lightsquared signals around 100+dB higher will not be solved. If Lightsquared did the decent thing and transmitted just from space at an appropriate power level then it wouldn't be a problem for GPS.
Regardless of the lack of real competition in the US mobile phone market, the sooner Lightsquared run out of money and go away the better IMHO.
If you will insist on transmitting with several orders of magnitude more power than your spectrum license permits then I'm not surprised the test were rigged to fail, lightsquared ensured that themselves when they let them have equipment to test.
Didn't they have a single electrical engineer on the books who had the balls to tell them that unless the laws of physics changed overnight their whole business model was fucked.
Whining that the Gubberment are against you when you were trying to pull a fast one is rather foolish.
And that "hedge" fund that didn't bother hedging is even more astounding. I think they are going to suffer the most when their clients find out what happened.
Certainly changed their tune since this plan first aired:
There should be no interference.
Ok,. there is inteference, so we'll change our plan
Ok, so the new plan has interference, we'll build filters
Ok, so there is interference, but it is the fault of the GPS people
Ok, there is interference, and everyone hass to accept it!
Ok, there is interference, but we've been authorized to make that interference since the year 1066
What interference? It is all based on rigged tesats!
Huge conspiracy! GPS causes cancer! Tinfoil hats to protect against GPS!
The major backer of Lightsquared was a big Obama donor. Letting him buy bandwidth for billions below cost (because it was sold as space only) and then getting the FCC to make it ground based was payback. They even pressured a General to testify it wouldn't interfere with GPS. The General refused and blew the lid off the scam.
"At a classified briefing, head of the Air Force Space Command Gen. William Shelton informed House members that he had been pressured to change prepared congressional testimony in order to better compliment a Virginia-based satellite and communications company funded by major Democratic donor Philip Falcone. The GOP has been wondering for some time now whether work done by that company, LightSquared, has been “unduly expedited” by the Obama administration in its push for nation-wide wireless network upgrades." http://www.mediaite.com/online/gen-shelton-asked-to-say-things-i-didnt-agree-with-on-dem-donors-company/
The main names behind lightsquared did donate money to to the democrats. They also donated as much or more to republicans.
Obama did own stock in Lightsquared (technically the company that became lightsquared) for something like 8 months back in 2005. He sold the stock for a loss.
If there has been any backroom influence here it is probably more because the lightsquared head of regulatory issues is ex FCC and so knows all the loopholes and who at the FCC to speak to.
The liberal Daily Beast reports on a broadband project backed by a frequent Obama White House visitor and donor that has Pentagon officials concerned over potential military GPS interference. The Obama FCC took the lead in intervening on the donor, billionaire hedge fund manager Philip Falcone’s, behalf and granting his company called “LightSquared” one of those coveted Obama waivers from existing law. Then Obama officials reportedly pressured a general to alter his testimony about the company’s impact on military satellite transmissions.
In a nutshell:
The four-star Air Force general who oversees U.S. Space Command walked into a highly secured room on Capitol Hill a week ago to give a classified briefing to lawmakers and staff, and dropped a surprise. Pressed by members, Gen. William Shelton said the White House tried to pressure him to change his testimony to make it more favorable to a company tied to a large Democratic donor.
The episode—confirmed by The Daily Beast in interviews with administration officials and the chairman of a congressional oversight committee—is the latest in a string of incidents that have given Republicans sudden fodder for questions about whether the Obama administration is politically interfering in routine government matters that affect donors or fundraisers. Already, the FBI and a House committee are investigating a federal loan guarantee to a now failed solar firm called Solyndra that is tied to a large Obama fundraiser.
Now the Pentagon has been raising concerns about a new wireless project by a satellite broadband company in Virginia called LightSquared, whose majority owner is an investment fund run by Democratic donor Philip Falcone. Gen. Shelton was originally scheduled to testify Aug. 3 to a House committee that the project would interfere with the military’s sensitive Global Positioning Satellite capabilities, which control automated driving directions and missile targeting, among other things.
According to officials familiar with the situation, Shelton’s prepared testimony was leaked in advance to the company. And the White House asked the general to alter the testimony to add two points: that the general supported the White House policy to add more broadband for commercial use; and that the Pentagon would try to resolve the questions around LightSquared with testing in just 90 days. Shelton chafed at the intervention, which seemed to soften the Pentagon’s position and might be viewed as helping the company as it tries to get the project launched, the officials said.
If the spectrum is used for its original purpose, eg. receiving satellite transmissions, interference problems should be negligible. Lightsquared didn't want to use it for that purpose, instead they wanted to transmit high powered signals at ground level; a very difference use. This is the heart of the problem.
Years ago I used to work on seismic survey boats. They all had 'talkback' systems - grab mikes and 100V line speakers all over the shop. People could grab a mike and say "the port tailbuoy is in the water" (or upside down) and people in the recording room could say "we are going to turn now" and everyone knew what was going on.
Then a new ship was planned and specified by an ex-naval commander. He had the speakers, but the only microphone was on the bridge. When challenged, he replied
"People on the back deck are told what to do. They don't have anything to say about it."
The level of jamming lightsquared think is OK is given as 8dB and then the jammer power was given as 32 times too high.
OK so the lightsquared press release used those units, it makes them look better, but why do all the media have to blindly repeat that rather than giving the two in the same units?
8dB jamming = 84% reduction in signal to noise ratio.
1dB jamming = 20% reduction in SNR
32 times too much power = 15dB too high. (or ~105dB over GPS rather than the ~90dB they now want to launch at). After launch they plan to increase power by 6dB (4 times) after a year or so.
(90dB = 10^9 or 1 billion times).
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