The LightSquared problem, time to join “Save Our GPS”?
When many readers sent me the GPS World article on GPS jamming, I was blasé. How could the U.S. government possibly allow LightSquared to put up 4,600 transcievers pumping broadband data services in the L band with such power that they’d significantly interfere with nearby GPS frequencies? As in complete failure at over half a mile for a high quality civilian GPS receiver like the nüvi 265W
Actually, it’s unlikely that the LightSquared transmitters will affect marine GPS because the company licensed the L Band spectrum from Inmarsat and apparently part of the deal is that the new equipment will be installed in such a way that it interferes minimally with regular Inmarsat service along our coasts (though filters may be needed on some Inmarsat terminals). However, boaters were among the first to adopt GPS and still tend to understand more than most about how it works and how critical it is to navigation. Which is why marine electronics manufacturers and users, plus safety-minded organizations like BoatUS, should consider joining the just-formed Coalition to Save Our GPS.
I’m impressed with the Coalition’s rational approach to the LightSquared issue and particularly its specific recommendations to the FCC. The concerns thus far may be based on lab testing — and some doubt the conclusions — but they’re certainly dire enough that the real world testing should be done with great care, and with plenty of opportunity for public input and for the FCC to change its mind without penalty. (Mind you that LS is a huge hedge fund bet in what’s already a wild west of ATC services.) As a Trimble VP noted to Congress on Friday, “Spectrum is a public asset and it should not lightly be handed over at the behest of a private party. More fundamentally, the laws of physics cannot be waived by the FCC. This is a serious problem with no obvious solution.” Panbo joined the Coalition today; how about you?
I’m impressed with the Coalition’s rational approach to the LightSquared issue and particularly its specific recommendations to the FCC. The concerns thus far may be based on lab testing — and some doubt the conclusions — but they’re certainly dire enough that the real world testing should be done with great care, and with plenty of opportunity for public input and for the FCC to change its mind without penalty. (Mind you that LS is a huge hedge fund bet in what’s already a wild west of ATC services.) As a Trimble VP noted to Congress on Friday, “Spectrum is a public asset and it should not lightly be handed over at the behest of a private party. More fundamentally, the laws of physics cannot be waived by the FCC. This is a serious problem with no obvious solution.” Panbo joined the Coalition today; how about you?
Ben, We are signing up Waterway Guide and getting the information out to our subscribers ASAP. Thanks, Chuck
And while this may not affect marine GPS, there are plenty of aquatic users outside the INMARSAT licensed spot beams.
Wonder what it does to GLONASS and Galileo?
Long time ago I was told anyone can shoot themselves in the foot, but people painting bull’s eyes on their instep deserve what they get. It appears our decision-makers(?) came to work with a paint-pot.
I love the quote at the bottom of “Inmarsat’s Chief Doubts Severity of LightSquared-GPS Interference Issue” where the chief is quoted “We’ve seen this before in the U.S. when [spectrum] users are going to get moved. Part of it is negotiation, to get the issues dealt with in a way they find commercially attractive.”
How could it ever be commercially attactive to provide everyone with new GPS receivers (with filters on them ??), either handheld, or mounted with costs covered to install them in every airplane, boat or car currently using them ?
Aaaahhh! the awesome power of commercial intere$ts!
In the good old days, somebody at the FCC would have been flayed and salted instead of commended for facilitating such an impressive bunch of numbers. Where do we stand in line for our Seventeen cent compensation check?
Given Homeland Security has enough problems without something like this perhaps they are a good proponent for putting the kabosh (a technical term) on this.
All law enforcement for that matter…
Technically speaking I believe that would be “kibosh” as in
ki·bosh [kahy-bosh, ki-bosh] put the kibosh on, to put an end to; squelch; check: Another such injury may put the kibosh on her athletic career.
Origin: 1830–40; of obscure origin
The bummer here is that it might be a good thing to have an alternate and competitive 4G broadband network, even if it made a Gordon-Gekko-like hedge fund manager even richer. And the weird thing is how this is being done in spectrum that’s suppossedly reserved for sat coms, but with the ATC loophole. My understanding is that LightSquared is putting up a satellite mainly to fulfill regulatory requirements, though it plans to do more than 99% of its 4G service on the ground.
The most effective way to take action is to write your Senators and Congressmen. A letter with a personal signature is most effective, but a large number of emails can prompt them to do some checking, and a Congressional Inquiry is guaranteed to give us civil servants pause to reconsider our transgressions!
For help doing this go to:
http://www.senate.gov/general/contact_information/senators_cfm.cfm
https://writerep.house.gov/writerep/welcome.shtml
Sorry, translation error. I’m a Texan and we say kybosh, I thought in New England one would pahk the kabosh in Havahd….
The first time some Congressional Representative or Senator discovers his/her in-car GPS unit directing him/her to drive through the Library of Congress, maybe this will get some serious attention. Or maybe it’ll take an airplane to crash into the Capitol Building. This represents the height of irresponsibility and creates entirely unnecessary dangers for so many people. It’s nice that Inmarsat leased the spectrum under conditions that minimize interference with its own services, but interference with a basic, vital public utility such as GPS should take precedence of such financial deals.
Some years ago, I was working for a company trying to push WIMAX to provide “last mile” broadband service to rural America. Unfortunately, the (then) over-hyped technology didn’t mature fast enough for us to access the capital required, and we moved on.
LightSquared is apparently giving it a go now that WIMAX is a bit further along. This isn’t just one company and there is already congressional involvement — on their side. This article may provide some additional insight. There is momentum and a constituency. LightSquared
snags Open Range as network partner
I will make a prediction: This cockameme decision will be reversed the first time that the pilot of a Senators or Congressman’s plane announces that he is unable to land at Smalltown airport because the RAIM circuit in his GPS alerts him that it is not accurate enough for a GPS instrument approach, and instead the passengers will be dropped off at Big City airport and left to fight traffic in rental cars to get home.
The effect on marine GPS is bad enough, but it is nothing compared to what it will do to aviation.
Ham radio operators, mobilized by the American Amateur Radio League (ARRL), fought and won a very similar battle with broadband over power lines (BPL). In this scheme, the FCC, as chief cheer leader for BPL, claimed no harmful interference would/did occur. ARRL volunteers, using their own laboratory equipment, proved beyond a technical shadow of a doubt, that harmful interference was occurring. After removing their head from the sand, the FCC finally shut down the BPL systems that they had licensed. For now.
Charlie
KS4VB
Let’s not forget that LightSquared interference has not yet been proven in the real world, and even the Coalition to Save Our GPS is only asking the FCC to be methodical about the testing and not to promise LightSquared something they shouldn’t reasonably have.
Incidentally, here’s another recent article on GPS jamming that’s gotten a lot of play: http://goo.gl/NKZ5q
Unfortunately its English author favors eLoran as backup but doesn’t seem aware that the technology is pooched here in the States.
Most Federal Agencies are headed by political appointees. It’s too much to expect the 4200+ jobs in the “Plum Book” to be filled with appointees who are technically qualified to make reasonable decisions in those positions. And they are politically sensitive to begin with.
They rely on staff to explain the implications of their actions, and are prey to less balanced and possibly more attractive solutions provided by biased outsiders. So too are some of the same staff who are supposed to be unbiased and objective in their recommendations, for any number of reasons both above and below expected standards of duty.
This is how mistakes are made. The first recourse available to the public lies with their representatives in Congress, preferably with those who do NOT serve on related committees. This is so they will have no predisposition to the question.
Our representatives are less sensitive to objective arguements than they are to large numbers of obections from their constituents.
So exercise your rights to vote with letters and email. Vote early, vote often, use aliases (g)
Ben,
Where I would hope the Coalition and others would bring influence to bear is on test design. Not only must these tests show no problems in normal operating environments/modes, they need to look at most likely failure modes and stressed environments (for both the BB and GPS systems).
And while I agree procedurally with Sandy, neither approach is sufficient unto itself. Legislators tend to need (really, really) smoking guns when their attention is as micro-parsed as it has become.
From my cursory reading on this topic, there are two issues:
–the frequency spectrum allocated to Lightsquared (or its predecessors) was originally allocated only for use in satellite communication, and, from this, one can infer that the price paid to obtain this spectrum by Lightsquared (or its predecessors) was much lower than if the available use of the spectrum at time of purchase permitted terrestrial mobile data relay. Thus FCC approval of re-purposed use of the spectrum represents an enormous financial windfall for Lightsquared and its investors; and
–the frequency spectrum being adjacent to the NAVSTAR GPS L1 carrier is liable to cause interference to existing GPS receivers. In general there is a policy of protecting existing users of spectrum from interference from new users of the spectrum, and the burden of providing the protection is usually on the new user. In this case it appears that Lightsquared proposes to mitigate interference problems by requiring the existing users of the spectrum to take some action.
The only reasonable conclusion that explains these unusual policies is that someone in our government is working over-time to further Lightsquared’s interests in this process at the expense of the citizens.
I confirmed with the BoatUS Legislative Affairs Office that they aware of the issue and have have sent a letter to the FCC on this subject.
Raul
The Economist is out with its own take on GPS vulnerability (thanks, Dan!): http://goo.gl/dzjQ2
Once again, eLoran is cited as viable back-up, and apparently DHS has to declare some sort of back up strategy next month. Could eLoran be resuscitated here in the States?
I hope you haven’t thrown away all you maps (big paper things)and turned your chart table into a TV lounge. Always keep a paper plot as backup and relearn DR (dead reckoning) just in case.
happy sailing
p.s. anyone got a Walker log for sale? (joking)
I’d hold off buying any expensive GPS dependent device until this receiver overload interference issue is resolved.
Following this debacle, you will become aware the FCC has made the Lightsquared network license waver conditional pending the outcome of effects testing. A catch here .. Lightsquared itself has been directed to organize and conduct the test.
Interestingly, Lightsquared must adhere to a network buildout schedule that has not been adjusted to account for attendant delays associated with the testing. So, a skeptic might reasonably conclude testing was ordered to appease FCC critics who cite unusual circumstances surrounding the waiver grant. In other words, the fix is in.
For those technically interested, pertinent test plan documents filed by Lightsquared attorneys are available at PNT.gov.
I’m thinking the international aviation community will be most adversely affected. Next generation air traffic control is almost totally GPS dependent.
Airborne GPS/WAAS equipments require wide receiver bandwidths to achieve stringent reliability and accuracy required for FAA certifications. An organization that sets these specifications has warned FCC this class of equipments is not designed to operate in the forthcoming electromagnetic environment. Over 100,000 airborne units are currently in service.
Fortunately, many interested government and commercial entities are conducting independent investigations. Perhaps, there’s a playable trump card to stop this outrage.
— CaptChas
Certainly Aviation will be affected, but so will:
Cellular telephony — system timing
Disaster relief/emergency services
Vehicle tracking systems,(UPS, FEDEX, etc^2) person tracking systems(Sex Offender, Bailee, etc), Valuable asset tracking (motion based security systems)
Geotagging
GPS tours
GPS Golf Carts!!!
Utility system phasor measurement units
Surveying
Tectonic Measurements–fault motion measurement
…and the beat goes on…La de da de de, la de da de da
So I ran into a field engineer for a big GPS company at the gym (it’s an odd little town in Maine), and he’s headed out to the White Sands Missile Range where Lightsquared will set up one of its transmitters so a group of engineers like him can try all sorts of GPS tests around it. He also said a GPS industry coalition has hired a big time DC law firm.
A good article on this subject
http://www.insidegnss.com/node/2508
I ran into that engineer again at the gym, and while the testing is complete, he can’t talk about the results. But he did tell me a little about the amazing RF anechoic chamber the U.S. Army spent 31 million dollars on a few years ago. It’s big enough to hold an Abrams tank, or maybe even a stealth helicopter. Details here:
http://www.thehowlandcompany.com/EMVAF.htm
He also said that an amazing array of GPS engineers showed up for the LightSquared interference testing and the report should be out soon.
This excerpt from the interference testing Working Group (TWG) second FCC report validates Ben’s discussions with the GPS engineer:
‘Radiated emissions testing (anechoic chamber) – testing of aviation receivers was performed by FAA personnel and contractors within a large anechoic chamber at WSMR, New Mexico. Simulated GPS signals were broadcast by one antenna within the facility, and emulated LightSquared base station signals were broadcast by another antenna. Aviation receivers were located within one area of the chamber, connected to appropriate antennas, and the outputs of the receivers logged as the LightSquared signal levels are varied. The FAA has not yet determined the extent to which test results for the non‐military aviation receivers tested would be made available to the TWG’.
The report goes into details about GPS avionics testing. It’s a complex process that would indeed require specialized talents of engineers, test technicians and statisticians.
According to the report, the live sky tower test will be conducted at Holloman Air Force Base. TWG will be conducting additional avionics testing.
— CaptChas
Some observations by emergency services personnel participating in live sky testing at the Holloman tower test site:
http://www.gpsworld.com/gnss-system/first-responders-lightsquared-issue-11620
Although somewhat lacking in technical rigor, these observations are adequate to confirm a Lightsquared/GPS compatibility issue.
— CaptChas
Further testing is slowly becoming public, and it doesn’t sound good:
http://www.insidegnss.com/node/2630
Looking over the Inside GNSS articles:
‘Some observers believe that LightSquared may attempt to divide the GPS community by trying to find solutions for the numerically small number of safety-of-life aviation and maritime applications, while convincing the FCC to require other GPS user groups to deal with interference problems on their own’.
That’s not so easy. I suppose ‘numerically small’ refers to 150,000 (plus) receivers that are in every day service flying airplanes around. There will need to be international agreement on engineering the modifications. Then the equipment will be tested for certification before allowing manufacturing or modifications to proceed. Maybe by 2016 (optimistic) hardened avionics can be fielded.
So, while this is happening, FAA withdraws thousands of GPS landing approaches and puts NextGen on hold while legions of phone zombie twits and tweets payout billions to Lightsquared.
I suppose maritime receivers refer to AIS equipment that presents similar logistical difficulties.
‘The National Space-Based PNT Executive Committee met Wednesday (May 11, 2011) to consider the analysis of early results from tests ordered by Russo separate from those undertaken in as a condition of the January 26 FCC order granting LightSquared a waiver on ATC limits. The ExCom has requested a meeting with White House, FCC, LightSquared, and other federal agency officials to discuss the situation’.
We all can see what’s going on here. Why is the ‘White House’ involved in a licensing matter that should be handled routinely by the FCC bureaucracy?
— CaptChas
Long before the test Lightsquared advanced the argument that the GPS signal per se would be unaffected, rather the GPS receivers are affected because the receivers were not designed to include the necessary filtering for a loud spectrum neighbor (probably not the right terminology). Inmarsat’s Chief was quoted “We’ve seen this before in the U.S. when [spectrum] users are going to get moved. Part of it is negotiation, to get the issues dealt with in a way they find commercially attractive.”
At first I was outraged (see my comment two months ago)
Now, I would wager Lightsquare will show up to future tests with slightly modified (by them) versions of consumer products to support there position.
So their point is “Part of it is negotiation, to get the issues dealt with in a way they find commercially attractive.”. What’s commercially attractive? Modify or provide new GPS’s for everyone, I don’t think so. For aircraft and emergency responders, maybe, but probably not even that.
There will also be tests I imagine for how much of the spectrum, if it went unused by Lightsquared, would be enough to reduce (not eliminate) the problem in the short term for todays products. How much can be tolerated, 1/16 mile 1/32 mile? Then they would likely negotiate how long they would not use that spectrum. Five years? Enough for aircraft receivers to be certified and replaced, reasonable for smartphones to reach end of life, but consumers in our industry keep their GPS’s much longer. Same for GPS’s embedded in automobiles.
How much spectrum will be left unused and for how long? Will anyone care in the short term if the problem is shifted to the long term and the government nets some new revenue, aircraft and emergency responders get upgraded equipment?
This should not surprise anyone. I think quite possibly this is heading in the direction of not being a big deal.
The FCC chairman responded to Lightsquared testing problems, but sounds a bit grouchy about it: http://goo.gl/IJ53P
He’s gotten himself in a real pickle. I’m sure he summarily dismissed advice from his technical staff, ‘I asked Lightsquared about GPS. They tested it and said there’s no problem’.
Lightsquared actually did test a few GPS enabled cell phone handsets. Did they really believe that was the scope of their problem?
Now watch for the forthcoming interference report for GPS avionics from the Radio Technical Commission for Aeronautics (RTCA).
The RTCA report is based on white Sands testing and, according to its executive summary, is expected to conclude:
‘The impact of a LightSquared upper channel spectrum deployment is expected to be complete loss of GPS receiver function’.
So spin that Mr Genachowski.
— CaptChas
GPS testing has surprise results according to John Deere company.
John Deere is participating in the GPS testing with some of their aggricultural equipment (not sure if that = gps guided tractor ?). They are claiming their high precision equipment is more sensitive to LightSquared transmission then consumer products, that their products are affected at a range of 22 miles, that their existing receivers cannot be modified, and future receivers will be difficult to design to both (1) filter lightsquared and (2) use future gps signals that span a wider frequency band.
http://www.gpsworld.com/machine-control-ag/precision-ag/john-deere-lightsquared-interference-report-11713
Precision Agriculture and PNT services is John Deere’s dog in this fight.
The GPS isn’t on the tractor, it’s on the sprayer. Precision Agriculture uses multispectral aerial photogrammetry to analyze the nutrient requirements of crops on a per-square foot basis. The information is downloaded into a Flash card which is then installed in the GPS controller on the nutrient sprayer implement. The farmer then “mows the lawn” while the sprayer applies the right amount of the right nutrients to each square foot of ground. John Deere is a major supplier of both Precision Ag services as well as PNT services used extensively by the construction business. These days you cannot grade a road without kinematic high-precision GPS guidance.
Deere’s top-line from PA and PNT was targetted to be at least $500million several years ago now.
Mike, I’ve read articles (sorry, but that was long enough ago that I don’t have links) that gave a second use of GPS for agriculture. In the effort to minimize erosion caused by breaking up the soil and allowing rain to wash the topsoil away, farmers are working hard to ensure that their furrows are as perpendicular as possible to the slope of the hillside. This implies that the tractors have to be guided very accurately, within a meter or two at worst, which does imply GPS receivers/displays on the tractors, as well as highly accurate topographical information (from satellites, more than from USGS maps).
The spin doctors are already at work here in Saint Petersburg, FL with daily full page ads by LightSquared extolling the incredible benefits that they are going to provide to all.
Per my earlier comment, this looks like the broadband over powerlines (BPL) game all over again with the FCC being a cheerleader rather than an objective, science based regulator.
Charlie
Wireless competition By Sanjiv Ahuja — He’s CEO of Lightsquared
That Lightsquared spin machine is worse than actually being seasick:
http://thehill.com/blogs/congress-blog/technology/164219-wireless-competition-?page=1#comments
The reader comments are really fun reading.
— CaptChas
I just received this email from Mary Hanley of Prism Public Affairs on the PNT Advisory Board Meeting today…..
FOR IMMEDIATE RELEASE: June 9, 2011
CONTACT: Prism Public Affairs
Dale Leibach: 202-207-3630 or [email protected]
Anne Tyrrell: 202-207-3632 or [email protected]
FCC Should Focus Its Efforts on Finding a Practical Way for LightSquared to Proceed
Tests Confirm Planned Network Will Cause Substantial Interference
WASHINGTON, D.C., June 9, 2011 – Speaking today at an event sponsored by the National Space-Based PNT Advisory Board, Trimble Vice President and General Counsel and founding member of the “Coalition to Save Our GPS” sent a strong message to the Federal Communications Commission (FCC):
“The test data discussed today makes clear that there is substantial interference to GPS if LightSquared turns on high-powered terrestrial facilities in the spectrum next door to GPS,” Kirkland said. “The data confirm what the industry told the FCC before it granted the waiver, and also confirms that there is no viable technical fix. It’s time for the FCC to stop squandering resources trying to find a solution to an unfixable problem. Instead, it should focus its efforts on finding spectrum that LightSquared can operate in –where LightSquared won’t interfere with GPS.
“When it comes to broadband and GPS, it’s not an either/or situation – the United States can, and should have both. LightSquared says it has other spectrum and it should use it,” Kirkland said.
At issue is an unusual waiver granted to LightSquared in January by the FCC’s International Bureau allowing the dramatic expansion of terrestrial use of the mobile satellite spectrum (MSS) immediately neighboring that of the GPS – utilizing extremely high-powered ground-based transmissions that tests have shown will cause interference to hundreds of millions of GPS receivers across the United States.
At the event, Kirkland and government representatives discussed testing conducted to measure interference to GPS receivers used in aviation and other critical government applications. In at least one test, LightSquared failed to deliver test equipment that matches its proposed operations, thus causing optimistic results – and even those optimistic results showed interference.
“It’s clearly a good thing that LightSquared is trying to do,” Kirkland said. “No one in the GPS industry opposes its goals of increasing wireless data capacity and competition, but the available data has shown overwhelming interference, and LightSquared should not be allowed to launch in the spectrum adjacent to GPS.”
A joint industry report is due to the FCC on June 15th, when the FCC will begin a public comment period before making its final decision.
Chuck
This Associated Press article ran in our local paper today in the Business Section:
http://tinyurl.com/3dzfdu2
Charlie
An update today in the Seattle Times, with a new plan…
http://seattletimes.nwsource.com/html/businesstechnology/2015374959_apustecgpsthreats.html?syndication=rss
I am not reassured given this quote: “Jim Kirkland, vice president and general counsel of Trimble Navigation Ltd., which makes GPS systems, called LightSquared’s new plan a “Hail Mary move.””
This is getting even more bazar. Now Lightsquared thinks that every GPS user in the US should pay to keep Lightsquared from rendering our equipment useless. For the full text go to:
http://www.avweb.com/eletter/archives/avflash/1940-full.html#204873
GPS FIRMS SHOULD PAY TO PREVENT INTERFERENCE: LIGHTSQUARED
LightSquared says the GPS industry should pay to shield its devices from interference its proposed network of wireless internet transmitters might cause. On Thursday, the company launched a counteroffensive in the increasingly acrimonious battle over the bandwidth it hopes to use for the nationwide wireless network of 40,000 towers. The GPS industry says tests prove the broadband network will disrupt GPS signals and is urging authorities to reject LightSquared’s proposal.
Man, this is getting serious. While I think it’s ridiculous for LightSquared to complain that the GPS industry is getting a free ride because the government pays for the satellites, I do see some logic in the notion that “…by failing to deploy receivers with sufficient filters, the GPS industry essentially uses LightSquared’s L-Band spectrum beyond the GPS allocation.” To keep the wonderful wheels of technological innovation spinning, we do need to make our spectrum usage as efficient as possible.
No, Ben. GPS usage of the assigned spectrum is polite and well mannered. Transmitting from ground towers at ludicrously high power is the problem, something specifically prohibited at the time the spectrum was allocated. LightSquared’s ultimate justification of this rape of the infrastructure is “its a 120 billion dollar thingie, and everybody loves big money”
445 12th Street SW must have just got some new carpeting, and the fumes have compromised their critical faculties. Or maybe there’s something in the water, ‘cuz these folks are just plain nuts.
Interestingly enough, my spell checker wants to substitute “disquiet” for LightSquared.
Someone should have to pay for all this provocation.
I disagree, Sandy. If cheap, simple filters really could mean that the spectrum adjacent to GPS could be used for providing alternate high speed data service, then current GPS receivers are not being well mannered.
I’m certainly not saying that LightSquared should be allowed to go ahead and force all current GPS users to upgrade. But maybe GPS manufacturers should be made to start using those filters ASAP, so that adjacent spectrum can be better utilized sometime in the future.
Ben,
The band in question is supposed to be for satellites, not high-power ground stations. If they want to deploy a ground-based network, let them buy the spectrum set aside for that use.
Ben: As I understand it, suitable filters don’t exist yet. This is just a pie-in-the-sky “solution” dreamed up by Lightsuared’s lobbying team. I suppose such a thing could be developed, but is it reasonable for the GPS industry to pay for this? Then what about existing GPS receivers? Including SPOT, we have four GPS receivers on our boat. Why should I have to pay to replace them when it is Lightsquareds scheme to use frequencies that interfere.
As for Lightsqueareds suggestion that GPS system users are somehow being “subsidized”, I should remind everyone that all of us US taxpayers paid for this system. If anyone is being “subsidized” it is foreign users, but they will not be affected by lightsquareds transmitters.
Quit this put a filter on and all is well nonsense.
Nobody is going to render a $25,000 avionics GPS receiver Lightsquared compatible with a 35 cent filter. These equipments are already filtered to meet requirements of internationally certified safety of life standards.
FCC is supposed to coordinate spectrum issues with NTIA. Evidently, NTIA knew nothing until DoD raised a red flag.
http://www.ntia.doc.gov/filings/2011/NTIA_FCCletter_01122011.pdf
The entire affair was to be ‘fast tracked’ and completed after a 10 day comment period spanning the Thanksgiving holidays. Then Lightsquared was to commence network buildout with trials this summer.
Did FCC Commissioner Genachowski have any idea he was about to rip open a hornet’s nest? I honestly believe Genachowski thought GPS enabled cell handsets and popular consumer devices were the technical scope of any GPS compatibility problem. He believed what he wanted to hear about the matter.
If he understood, would arrogance have driven him to take on the entire GPS industry with it’s billion customers?
— CaptChas
Ben- A significant update
The House Appropriations Committee today approved the fiscal year 2012 Financial Services and General Government Appropriations bill. One amendment to the bill prohibits funding for the Federal Communications Commission (FCC) to remove conditions on or permit certain commercial broadband operations until the FCC has resolved concerns of harmful interference by these operations on GPS devices. The amendment was adopted on a voice vote.
According to an eWeek news analysis, the prohibition means that the FCC is effectively barred from any further consideration of LightSquared’s plan, since even meeting to discuss the plan spends federal funds through employee salaries. Until LightSquared comes up with a plan that completely protects existing GPS navigation devices from interference, LightSquared cannot operate its satellite-based broadband service.
Just released today.
Full House still has to vote.
Senate has to vote its version.
Conference has to resolve differences.
President has to sign.
None of the above has happened on time in quite some time.
Continuing resolution will have to have the prohibition or nothing changes.
Current FY is funded through 30 Sep, HAC voice vote does not impact this at all.
From now until 30 September much mischief can be done.
GPS is a strategic asset, like the Strategic Petroleum Reserve. The SPR has been used tactically and politically more than once, don’t discount that GPS might be as well.
Question for someone seriously familiar with the physics involved in filtering such signals … What is the truth about filters?
a) They could have been incorporated into previous consumer GPS devices / can be incorporated into future consumer GPS devices for 35 cents a device ? For some reasonable amount more than 35 cents ?
b) It is impossible [for a consumer grade device] to create a filter for such a noisy spectrum neighbor and still hear the very low powered signal in the GPS band ?
c)It is impossible [for high precision GPS receivers only, e.g. farming equipment ] to create a filter for such a noisy spectrum neighbor and still hear the very low powered signal in the GPS band ?
d) If Lightsquare leaves the spectrum immediatly adjacent to GPS unused for a time (their recent proposal), the power they plan to use in the spectrum nearby is still to noisy for high precision GPS even with new filters ? (Or is it only to noisy because there is another non-GPS signal in the next band over used by farming equipment that would be interfered with?
e) If Lightsquare leaves the spectrum immediatly adjacent to GPS unused for a time (their recent proposal), consumer grade GPS receivers will work fine?
How could this bizarre situation arise? Can it be explained without pointing a slandering finger? With objective evidence overwhelmingly opposing the notion, how does it continue to monopolize the time and effort of so many? In short, what or who is driving this apparent piracy? Shouldn’t alarms be ringing at agencies tasked with investigating situations like this? Where is J. Edgar when you really want him?
By international agreement, the satellite radio navigation band spans 1559 – 1610 MHz. GPS transmits on 1575.42 MHz. By design GPS signal spectrum spreads to the satellite band edges. Military P and M codes have even more significant spectral power components extending to the lower band edge. High precision civil and military equipments require reception of the entire satellite band capturing the entire GPS power to meet design requirements.
Lightsquared wants to operate a 10 Mhz wide channel centered on 1550.2 MHz. This channel will have an effective radiated power of 1500 watts. Say about 500 meters from the tower, that signal can indeed be ‘a billion’ (90 dB) times more powerful than GPS. Without adequate adjacent band filtering, the network signal will seize the front end of the GPS receiver. That’s the physics.
It’s a basic dynamic range problem designing a filter that ‘rolls off’ by factor of a billion (90 dB) within the guard band residing between 1559 and upper limit of the network channel at 1555.2 Mhz.
Mitigating receiver performance degradation, the filter would need to exhibit a low insertion loss while not distorting the time relationships of the GPS spectral components through a effect known as group delay .. more physics!
It also must physically fit into its space claim. Then preventing signal ‘leakage’ around such a shape factor filter requires extensive shielding. That’s also physics.
A 35 cent Surface Acoustic Wave (SAW) cannot even come close. Contrary to the cheaply made receiver argument, most consumer GPS receivers do have SAW filters.
Mr Straub (Garmin) presentation before the congressional committee and FCC engineering .. his discussion about filters is presented in Section VII.
http://licensing.fcc.gov/myibfs/download.do?attachment_key=900010
Note the arguments pertain to aviation receivers. I’ve been contending Lightsquared must get past the FAA before they can operate. If they cannot operate, the problem is solved for us all.
We don’t know how Lightsquared will affect our consumer quality devices. That can be discussed after the final interference report is released.
As low accuracy accuracy users, our receivers don’t require full band GPS signal components. Perhaps a filtering solution is more feasible for us.
We will not know the effects on military equipment. Perhaps they have access to classified filter technologies .. but I doubt that.
— CaptChas
The question was asked essentially “How can this obvious threat to GPS be allowed to proceed?” Believe it or not it is a combination of White House policy and cooperation with companies offering to immediately implement WH Policy. Specifically – The NIIA was directed to “Find” 500 MHz of bandwidth in existing designated bands to provide to suppliers of Wifi communications capability (http://www.broadband.gov/) will show you the “plan”.
Currently not only GPS but all Commercial Radio Altimeters currently carried on every commercial passenger airceaft is also being threatened with 40 MHz of bandwidth being removed (20 MHz on each end of the 4.2 – 4.4 GHz Band) and assigning it to WiFi systems on the ground. There are already major efforts on the part of Boeing, Aribus and several avionics manufacturers to rebut this attempt as any use of this band by WiFi systems will jam altimeters and place the flying public at risk.
The NTIA did not consult the aviation industry before “fast tracking” this 40 MHz bandwidth due to an incorrect technical assumption. So GPS is not the only band that is at risk that also poses a threat to safety of flight. Its important to note that in addition to the US, the UK and France are also considering the same changes – I believe based on the same faulty technical information that began at the NTIA.
So how can these things happen? Government muscle with businesses that are aided by the rule making policies of the FCC / WH / NTIA. LightSquared is but a small part of an overall “plan” for expanded broadband access.
Gee thanks Dave. That makes it worse. While its all wrapped up in warm-fuzzies about letting Doctors see my xrays on their cell phones (!!?!) and bringing broadband to the hinterlands, its really so somebody can sell movies so people can watch them on a 3″ screen. That comes with a small price to pay; a few large smoking holes dotted here and there around major airports, a few oil slicks in busy harbors, one or two train wrecks, and a host of mis-delivered new 4G phones….
Call your Congressional Representatives and tell them you’ve changed your mind; this LightSquared thing is yummy.
Well the Lightsquared spin is available online at http://www.lightsquared.com/wp-content/uploads/2011/06/LS-Recommendation-and-Tech-Appendix-6-30-11-FINAL.pdf now. I won’t claim to have read it all yet, but from my quick scan through it might be summarized as “the GPS industry are a bunch of lazy bums and it is their fault that their crappy designs won’t work with our network, and our network is essential to the preservation of humanity.” Or something like that… 🙂
It appears that LightSquared Investors are desserting the ship in major numbers. See http://online.wsj.com/article/SB10001424052702304803104576428420093360188.html?mod=googlenews_wsj
This Wall Street journal July 5, 2011 article describes rapidly declining support for LightSquared by major investors in the Hedge Funds that support it.
Investors have been bailing out of Harbinger for a while. From June 8
http://www.bloomberg.com/news/2011-06-08/falcone-s-harbinger-said-to-face-1-billion-in-redemptions-as-assets-fall.html
This article is from last night. Reporter Amy Or says
“Peter Jenson has resigned as chief operating officer and director.
The 46-year-old’s departure, disclosed in a regulatory filing, came as the fund manager wrestles with redemptions and a controversial investment in LightSquared Inc., a start-up satellite wireless-network company in which Harbinger has invested.”
She continues
“Harbinger Capital was recently hit with investor requests to withdraw about $1 billion invested in its funds, people familiar with the situation told The Wall Street Journal in June. Harbinger told investors withdrawing money that they would be paid in part with stakes in LightSquared, the Journal said. Harbinger has shrunk to about $6 billion in assets from a peak of $26 billion in 2008, the paper said.”
This is from Last night’s on line Wall Street Journal.
FCC Working Group Recommends Against LightSquared in L Band – Recommends vacating the proposed frequency – See full report –
http://licensing.fcc.gov/myibfs/download.do?attachment_key=900848
Thanks, Dave! But I’m not sure that it’s fair to say what the working group recommends as so much of the report is divided up between GPS Community conclusions and LightSquared conclusions. It’s sure easy to see why investors might be bailing out of LightSquared, though!
The report is quite a piece of work, I think. It’s amazing how much testing and arguing got done in a short period, and I think it’s a testament to how industry and government can work through a knotty issue.
I also note that LightSquared’s call for filtering may be pretty farfetched as the GPS Community concluded:
“Several simulated filters were proposed as options for GPS receivers; however, no testing could be performed since these parts do not exist. While claiming marginal improvements in rejection of the LightSquared signals, these simulated filters did so at the expense of increased degradation of GPS signals. As a result of these efforts, the General Location/Navigation sub-team has concluded that no mitigations exist for the existing user base or for future products as long LightSquared remains in the MSS L-band. The only option for coexistence with GPS is for LightSquared to move to another frequency band.”
I also got a kick out the report’s first illustration, on page 18. While the text is pretty dry stuff, someone had the moxie to use Washington DC for a graphic example of where GPS would be jammed if the FCC’s orginal LightSquared power recommendations became real. The jammed area includes FCC headquarters and Reagan Airport!
PS Some more good DC-centered test graphics here:
http://www.pnt.gov/advisory/2011/06/bunce.pdf
Ben-
It gets much worse than just the FCC WG. Most of my news on this topic comes from one of the major GNSS websites that tracks this very closely – check this link for many other issues that will only give more fuel to Investors pulling out of LightSquared. I think the financial issues may soon crush this proposal. The FCC chair is going to have to overcome huge industry evidence – as seen at this link:
http://www.gpsworld.com/content/search?keywords=lightsquared
The game is not over. It seems obvious to me that LightSquared will “Plea Bargain” for use of the “Lower Ten” and has been inserting semi-technical “Yes-Buts” at strategic points to confuse the regulators. I hope some attention will be given to preventing such an end run by educating the decision makers before the proposal is pushed.
Somehow FCC was expecting that working group testing would conclusively prove there is no GPS interference problem. Inconveniently for them, the report confirms what is and should have been obvious before anyone embarked into this fiasco.
Perhaps the problem technical specifics are now understood. I think that’s the most Lightsquared, the GPS industry and FCC can conclude from their massive effort. I didn’t find anything outstanding proving the full and complete LTE network can proceed as scheduled.
Dropping back to regroup, Lightsquared claims they can solve the interference for 99.5% of GPS users by rephrasing their LTE rollout. Are they expecting the rest of us to sacrifice that 0.5% who rely upon GPS for ‘unimportant’ purposes such as growing food, surveying our land, constructing infrastructure and monitoring the movement of tectonic plates? That’s their new but rather evil spirited tack.
So, lacking a solution founded in credible science, this entire matter is trending towards red herring arguments. Who has ‘grandfathered’ rights to operate? Which technology will save more lives? Which technology is a more robust ‘jobs program’? Which technology generates more output to the GDP?
It’s to be an ugly fight evolving players at the highest level of government.
— CaptChas
This is scary stuff:
From http://www.politico.com/news/stories/0711/58832.html
“The LightSquared vs. GPS fight is an example of growing “border disputes” between companies who end up as neighbors on the increasingly crowded airwaves, said a senior FCC official.
GPS companies, which were using the airwaves first, have receivers that can pick up signals in adjacent frequencies, meaning they can be sensitive to signals sent by LightSquared’s equipment.
“There is a little bit of a problem having standards on transmitters and not on receivers,” the official said, adding that allowing incumbents with receivers who bleed outside their airwaves to “squish the property rights of their neighbors” is not a good precedent.”
Well, it looks like we’ve got our work cut out for us. I just read (and commented on) the following article: http://www.huffingtonpost.com/the-center-for-public-integrity/politically-connected-lig_b_902421.html, which states that the FCC has approved LightSquared’s license.
Actually, Jim, that seems to be rehashed and sensationalized old news. I’m all for expanded broadband, too; who isn’t? But the FCC decisions referenced in that piece took place on March 26, 2010, and Jan. 26, 2011. The story has changed a great deal since then. The test results are undeniable, and LightSquared is on the defensive. The story now is about whether they can salvage anything.
That headline is misleading. The current FCC/Lightsquared scheme is to allow public comment on the interference report, close the comment period at the end of July and then approve Lightsquared’s license.
— CaptChas
Ben, thanks for pointing that out. I misinterpreted the article as being new information and didn’t recognize that the dates mentioned were the whole content of the story. Sorry for the overly pessimistic alarm. But at least the story is reaching a wider audience now, if rather delayed.
The European Commission has opposed LightSquareds plans because of interference with Europe’s Galileo system. In a letter to the FCC, the EC has pointed out that approval of Lightsquards licence will violate a treaty the US has signed that forbids one county from interfering with radio signals from another.
http://www.avweb.com/pdf/european-commission_lightsquared-letter.pdf
Ben- Its time to write the Senate and House Members NOW! Please see the latest article just posted on GPS World Magazine Web site:
http://www.gpsworld.com/gnss-system/gps-and-gnss-cannot-count-good-sense-government-11921?
Unless congress acts, “the fix is in” and corruption in government will cause unbelievable harm. The talking heads are focused understandably on the Debt Crisis but they are about to ram this through regardless of technical facts.
The details provided in this article are very disturbing.
So what if we have to buy another GPS Sensor for $100 that has better filtering? Cheap GPS Receivers have relied on spectrum outside of the allotted GPS spectrum for years. Cell Phones already have GPS receivers that work with Light Squared!!
I’d rather have the competition to the other 4G services so that I can get cheap internet access anywhere in the U.S. Light Squared will also bring down the cost of our cell phone bills and over the course of a year or two more than make up the difference of a new GPS receiver. A new Garmin or TomTom can be purchased for less than $100. Adding a better GPS receiver will add almost nothing to this price.
SHILL ALERT! SHILL ALERT! The preceding message can ONLY come from someone practiced in the art of misrepresentation, misdirection, and spin doctoring.
This is NOT about cell phone A-GPS, or $100 car gps’, its about $4500 MFDs and 15 year old “Old Reliables” on boats that can’t afford replacing them. It’s about turning off several crucial industries that rely on the “Lower 10” for surveying, agiculture, soil erosion management, and more.
What’s absolutely unforgivable is the lie about filters. There are NONE. They haven’t been invented. They won’t cost a hundred dollars when the arrive, or even a thousand because they will be bleeding edge technology built in very small numbers.
This crap about “receiver filters” is THE BIG LIE.
This crap about how GPS has somehow been using frequencies out of its allocation is THE BIG LIE.
There are no “filters” for GPS receivers because THERE CANNOT BE! It’s not that they just DON’T EXIST, they CANNOT EXIST.
The entire L band was created EXPLICITLY and ONLY for signals traveling between a satellite and a ground terminal. NOWHERE is there any authorization for purely terrestrial traffic. There is NO legal way for BlightSkrod to operate in L-Band *anywhere* in the world.
Moreover, GPS does not have a single “frequency”, or even several frequencies. GPS works because of a technique called “Spread Spectrum” modulation. The signal is spread across a continuous range of frequencies. While there are energy peaks at several frequencies, all of the radiated energy is within L-Band and completely in compliance with the international allocation for L-Band. The quality of a fix provided by a GPS receiver is largely driven by how much of the GPS frequency RANGE it can receive. High-precision receivers, like used to guide aircraft, MUST receive the entire frequency range to perform as specified. This absolutely includes the range of frequencies which would be blanked by the BlightSkrod ground stations blasting away with a signal a few billion times more powerful than the GPS signal. Since the GPS signal and the ground station signals OCCUPY THE SAME FREQUENCIES, it is NOT POSSIBLE to “filter” only the ground station signals and leave the GPS signals undisturbed because it is not possible to determine which signal is the desired one. ALL signals in the filter passband are attenuated the same way. A filter cannot make this kind of distinction.
This is just like the legislature that tried to legislate the value of Pi to be 3.0 because it would be so much more convenient. The lying scumbuckets can say anything they want, but it does not change the laws of physics. The one rule that is ignored at your peril reads:
“Nature neither seeks nor abides your opinion.”
I get a chuckle from those who speak as if Lightsquared will provide ‘cheap’ broadband. Almost like they’re giving it away.
Consider their business model. They will be a wholesaler selling bits to telecoms but they will offer no services under their own trademark.
What does that mean? Well it means those evil telecoms like ATT and Verizon will buy Lightsquared’s bits and sell them to you. Rest assured, they will still charge you every penny the market will bear.
Lightsquared already has a huge business deal with Sprint in the works. Doe’s anyone actually expect Sprint to offer anyone cheap service?
— CaptChas
Phil Falcone, the hedge fund guy behind LightSquared, made his case on CNBC today. Among other things: “We’re not interfering with GPS; they’re interfering with us.”
http://goo.gl/73TSw
Monday, 8/15, is the deadline for filing comments about the LightSquared issue with the FCC. Here are instructions for how to do it, and suggested topics from Save Our GPS:
How to File a Comment with the FCC:
The FCC has an easy-to-use portal on its website to submit feedback on the testing results:
(1) Click on this link for the FCC’s Electronic Comments Filing System (ECFS): http://fjallfoss.fcc.gov/ecfs/upload/begin?procName=&filedFrom=X [In the case that URLs change, please make sure you are in the EXPRESS filings page]
(2) In the box which says “Proceeding Number,” type: 11-109. It is VERY important to include this docket number with your comments.
(3) In the designated boxes, enter (a) your name or your company’s name, and (b) your mailing address/city/state/zip.
(4) In the box which says “Type in or paste your brief comments,” do so. Click “Continue.”
(5) A review page will load listing all of the information entered. If correct, click “Confirm.” (6) If you have trouble, contact the FCC ECFS Helpdesk at 202-418-0193 or e-mail it at [email protected].
Suggested Comment Points:
Everyone who cares about GPS should let the FCC know about the threat that LightSquared poses. In writing to the FCC, we encourage you to cover the following points in your own words:
* How you use GPS technology in your business and/or personal life
* What would happen to your business/personal life if GPS became unavailable or unreliable
* While more capacity for wireless broadband services is important, it should not come at the expense of GPS, which is critical to our country’s economy
* The results of the testing that were performed at the FCC’s request are conclusive – they show that GPS reception would be wiped out by LightSquared’s proposed service.
* Now that the test results have shown interference to GPS, the FCC shouldn’t allow LightSquared to keep trying out modified versions of its plan to use the spectrum near the GPS band. LightSquared’s operations and GPS are fundamentally incompatible and the FCC should order LightSquared out of that band.
Ligthsquared news: General Reported He Was Pressured on Testimony About White House-Backed Project, Sources Say
Read more: http://www.foxnews.com/politics/2011/09/15/general-reportedly-said-was-pressured-to-change-testimony-on-white-house-backed
I think it’s a shame that this issue is getting politicized by Fox and others, even if it would a good thing to stop Lightsquared completely. Here’s a bit on how slanted the Fox story is: http://goo.gl/jCxpo
That’s not to say that it isn’t pretty disgusting to read messages from Lightsquared flacks to the Whitehouse suggesting that a good time to meet might be after a fundraiser their CEO was going to ( http://goo.gl/nOouz ). But that is SOP in Washington, and there’s no denying that Obama was in a favor of expanding broadband communications from the git go. In fact, I think we’d all be for Lightsquared’s plan to cover 260 million Americans, if GPS wasn’t involved.
I think the most interesting angle, unfortunately obscured by politics, is that the GPS community may see a way to work with Lightsquared’s revised proposal to just use lower spectrum, at least according to this analysis: http://goo.gl/A7gbP
I have lived in the Washington DC environs since 1980. The media doesn’t have to lift a finger to politicize things. If any government agency or actor is involved, ipso facto, it’s political and if anyone begins to lose traction on an issue or position, facts are set aside for rant.
We are just more exposed to the rant today than we were when we all griped about the Washington Post and Times…
Disclosure, I worked in government until 1997. I was part of the GPS program management team. I served and went to school with General Shelton…
Our new air traffic control system depends upon GPS. A multiplicity of emergency services depend upon GPS. Modern agriculture and other industries have come to depend upon GPS accuracy. Someone comes along and buys a frequency spectrum band licensed for low-powered satellited based transmissions. Then they expand this use to terrestrial transmitters with higher output. Meanwhile, there is an Administration policy to expand broadband to reach rural areas. Under this umbrella policy, this company intends to improperly expand coverage while interfering with an existing essential national service. Representative of the company and its primary financial backer lie about every facet of their operation. Congressional replies to constituents resemble company press releases.
What’s not to like? OMB review of prepared Congressional testimony is routine. Suggesting that an Air Force Agency shrink its test plan to 90 days betrays intent and bias. This stinks and the fact that it still is being debated is a clear demonstration of the power of money in our governmental processes. What is not being taken into account is the cost to the government at a time when there is an alleged focus upon the budget.
Ben, this is not a time for even-handed observations, it is a time for outrage. But, it is a great example of the dysfunction in our government.
If an external party disrupted CONUS-wide GPS availability to the same degree as LightSquared’s plans will, it would be considered an act of war.
If that is so, what term should be applied to LightSquared’s intended actions?
I may be naive but I feel no outrage about this situation. It seems to me that the very difficult but important business of regulating wireless spectrum in a rapidly changing world is happening right before our eyes, and so far it’s working OK. When I wrote the original entry last March I felt that Lightsquared would not be allowed to proceed if its transmissions really would significantly degrade GPS, and I see no evidence that it will.
A powerful coalition of GPS stakeholders (little Panbo included) got together to publically challenge Lightsquared’s plan, elaborate tests were conducted, and Lightsquared has backed away from the original proposal. I agree with Ron that Lightsquared has made some obnoxious and ridiculous statements along the way, but I doubt that was a wise strategy.
But I don’t agree that the spectrum Lightsquared licensed must always be used for satellite communications simply because that’s what it was originally allocated for. Good planning in changing times means you have to be willing to change plans. Now if in fact Lightsquared’s proposed change of use can not be tolerated by adjacent spectrum for solid technological reasons, that’s an excellent reason to deny them FCC approval. But apparently that remains to be seen regarding “the lower band”, if there’s any truth in the article I linked to above, called “A compromise between LightSquared and GPS industry may be possible”. Ron, Chris, and others, what do you think of Kevin Fitchard’s analysis? http://goo.gl/A7gbP
If GPS and new broadband data spectrum can coexist successfully, wouldn’t that be a good thing? I think so, and if it is possible it’s going to take science-based decision-making and a rational regulatory process to get there. And I’d like to think that despite all the messiness, a rational process is bumping along here.
PS I fear that Mike’s absurd suggestion that Lightsquared’s proposal is an “act of war” shows that over-the-top voter anger can be as antithetical to a rational regulatory process as partisan politics, special interest political contributions, and corporate lies.
Bravo Ben, Very well stated. CDhuck
Kevin’s analysis really sounds like someone looking for hopeful signs. I agree that if Lightsquared moves to the opposite end of its allocated bandwidth, and if that eliminates interference with vital systems, then of course those representing GPS interests should back off. But there must be hard, public, empirical data at every stage to permit a roll-out of a new service. Under no circumstance can any new service be permitted to interfere in any way with the FAA’s developing, new Air Traffic Control System.
The spectrum was purchased relatively cheaply because it was for a satellite-only based use. It’s a boon to investors if they can then hijack this spectrum into terrestrial use as well. It’s the bait and switch that ticks me off.
Ben, as you well know, electronics manufacturers must adhere to minimum FCC standards. Nothing compels them to conform to DOD advice. It is my *impression* that international receiver standards are more strict. At some point, there should be only one standard for a global system.
Interestingly, the Air Force proponent for GPS must be concerned about the more precise military GPS system which, in some cases, uses different satellites. I am guessing that military GPS sits even closer to Lightsquared’s spectrum. Remember, the Air Force testimony was given in a classified session. There is too much at stake here for this question to be rushed for a commercial interest.
I am convinced that the politicians involved have no idea what is at stake. If they did, Senators and Congressman wouldn’t be responding to constituents with Lightsquared pap. It is this shallow examination of most issues that continues to concern me.
Bravo Ron.
I think a point that has to be stressed here is that the original concept of re-using the satellite designated band could have and should have been analyzed for its potential to cause interference before the purchase was made. The major aerospace companies I have worked for would have conducted extensive internal due diligence before ever raising such an issue externally.
As an Aerospace fellow I deeply resent the comments made by Lightsquared regarding GPS receivers having been designed “illegally”. These childish statements can only be made by management types bent on getting their way with sheer force of will.
Aviation receivers are designed to be used with specific antennas that incorporate state of the art interference rejection filters specifically to reject out of band power from aircraft transmitters and HIRF (High Intensity Radio Frequency) energy. I have helped run the tests that apply 3000 Volts per meter field strength against our antennas and receivers to validate our rejection of interference.
But GPS receivers are based on Spread Spectrum modulaiton methods and accuracy of the GPS measurements are directly proportional to the fractional bandwidth of the TRANSMITTED SIGNAL that the receivers capture. AVIATION Receivers MUST MEET ACCURACY REQUIREMENTS and MUST acquire the proper transmitted signal bandwidth or they cannot be sold! There is ZERO technical merit to making a receiver input wider than is necessary to capture the original transmitted bandwidth because the added noise power reduces sensitivity. Thus L^2 statements that GPS reeivers had “stolen” bandwidth with “immorally wide receiver bandwidths” defies the laws of physics and is beyond comprehension as a fabricated public relations attack on the GPS industry and is a LIE!
Ben I could understand your statement implying that they are really just good guys and if we just settle down and let things progress normally all will be just fine, but the wildly inaccurate statements made by Lightsquared executives accusing the aerospace industry of cheating on designs and using bandwidth it had no right to is over the top. Couple those outright lies with statements that filters could be made (or should have been made) available to remove the interfrence is another lie and is not based on engineering reality.
So when you dismiss the statement that the Lightsquared technical approach is an act of war as way over the top – you give L^2 a totally free pass on THEIR totally irresponsible statements. If L^2 had maintained a solid technical approach and always provided analysis and due diligence measurements from the start, then Ben your comments would be valid and your claim that opponents to this spectrum grab are out of line would be beyond reproach. But believe me – as I posted before, the L^2 problem for GPS is just the tip of the 500 MHz Broadband Initiative iceberg. There is no huge public outcry about the 40 MHz they are trying to steal from the Radar Alimeter band but that re-use of bandwidth also places every transport aircraft in the US at risk on final approach due to WiFi jamming.
So Ben I totally reject the notion that the political powers involved have our best interests at heart. This is ALL about power and political influence because if the engineering work had been done properly from the beginning the concepts they are pushing would never have seen the light of day. So while on the one hand it is conceptually nice to say that gee its a good thing to want to re-use un-used or underutilized spectrun for the greater good, that is only true if the proposed changes are evaluated FIRST with sound engineering analysis and THEN AND ONLY THEN when it is clear that there is only minor chance that consequential interference will occur – THEN – the proposals should be put forth.
IF L^2 was a truly solid organization beyond challenge then they would have contracted with the GPS industry (Aviation and Precision Receivers at a mimimum) to pre-test / analyze the proposed concepts. They would have learned from that interchange that only the lower band had any chance of working and even that band may need mitigation. ALL BEFORE PURCHASING the rights to the spectrum.
You also have to consider the nature of the “act of war” comment – it was a SUPPOSITION – it was a QUESTION making a point. The point being that the ferocity of the arguments by L^2 against the GPS industry with major safety of life issues at risk is a direct indication that they have no regard for the honest and valid techncal data that has been provided by multiple agencies that all lead to the same conclusion – the L^2 use of the band is unworkable. These false statements and accusations against an entire heavily regulated industry is beyond the pale and can only occur if it was believed from the beginning that sheer political power would win the day and technical data was of no concern.
Any entity that makes such a blatant attempt to usurp such a huge national resource is the ultimate in arrogance and egotism. I am deeply offended by the dismissal of the serious technical points that have been made on this blog as being political rant. The FACTS and LAWS OF PHYSICS say that if L^2 and the NIIA and FCC had been operating with pure intent and the highest moral character with solid engineering analysis, NONE of the storm we have seen erupt ever would have happened. This is not good government and its not based on good engineering or high moral character and intent.
Dave, please don’t put words in my mouth. For instance, I certainly didn’t say that everyone involved looks like “good guys” but I did say that Lightsquared “has made some obnoxious and ridiculous statements”, which you seem to have ignored.
Nor did I speak at all to Lightsquared’s developement process. I thoroughly agree that they should have done their own testing and analysis before licensing spectrum, and I don’t give a damn if they lose their investment entirely. But that should only happen because their concept is technologically impossible, not because their bullying rhetoric has enraged the GPS community.
PS It really would be an act of war if some entity fragged our GPS system by surprise. But Lightsquared, as obnoxious as it may be, did not do that. Not one GPS of any kind has been affected by Lightsquared transmitters to my knowledge. Instead a messy approval, or disapproval, process is underway. What’s going on here is not war, it’s our capitalistic democracy at work. I think, or at least hope, that the parties who speak truth clearly and strongly — not BS like “war” or “immorally wide receiver bandwidths” — will have their way.
Ben,
Please don’t put words in my mouth either.
I made no such assertion about L^2.
What I asked was a real question about how L^2’s
stated plans should be viewed given the disruption
those plans are *known* to cause if implemented.
Your suggestion about “willingness to change plans”
is irrelevant in the face of the physics involved.
Nature cares not one whit about anyone’s opinion,
not even federal bureaucrats, judges, or lawyers.
As for “absurd statements”, I have neither the energy
nor the talent to match absurdities with the torrent of outrageous
fabrications spewing forth from L^2’s Big Lie machine.
I know when I’m outgunned.
Cheers,
– mo
I thought it might be useful to read GEN Shelton’s prepared statement to the Congress. It was just released.
http://tinyurl.com/6l8oloj
Last week LightSquared posted a flashy and expensive full page ad in the Wall Street Journal defending their “rights” to do what they do. It is obviously a bid to win the battle through media-driven popular opinion, and to heck with the marine users.
I believe the change in tone Kevin Fitchard wrote about is not a leading indicator of compromise over the lower 10 Mhz. Both sides in this argument have questioned the motives of the other, the GPS side more harshly than L^2. My analysis is that the GPS folks have refined their arguments and dialed things back a bit so they come across almost as cool and collected as Phil Falcone. That’s all.
It helps the gps folks that they have successfully (after how many months or years ???) found a non-technical way to communicate the incompatibility to non-technical people in our government that make these decisions.
General Shelton’s statement to Congress lists the many critical users whose GPS receivers would be put out of commission by Lightsquared’s current proposal. He also gently casts doubt on the likelihood of their being a technological fix. According to his interpretation of testing to date, no proposed Lightsquared change will relieve the conflict.
I have provided a URL for the prepared testimony above. There is not a single ray of hope in it for Lightsquared’s project; although he remains open to any solution they might come up with.
Perhaps the Lightsquared favouritism is going to backfire on Obama after all
http://thehill.com/blogs/blog-briefing-room/news/182553-issa-to-investigate-government-loan-programs
New Lightsquared press release:
http://www.lightsquared.com/press-room/press-releases/
“LightSquared Announces Simple, Affordable Solution to GPS Interference Issues”
I’ve got this bridge in Brooklyn.
LightSquared in hostile territory: Next Wednesday a representative will address the GMDSS Task Force meeting that will take place at the NMEA conference:
http://goo.gl/14dpR
…and I’ll be there.
I wonder if LightSquared is another Solyndra. They seem to get a lot of political help and influence. Here is their latest way of addressing the GPS issue. Unfortunately, it doesn’t address our concerns.
http://www.lightsquared.com/press-room/press-releases/lightsquared-announces-simple-affordable-solution-to-gps-interference-issues/
The September 13 response from FCC (see http://transition.fcc.gov/Daily_Releases/Daily_Business/2011/db0913/DA-11-1537A1.pdf ) seems to be trying to spread the blame for the failure of LightSquared’s Chucklehead proposal to the NTIA and the FAA. That smells like the end of the story.
The Coalition to Save Our GPS does not sound very compromising in this recent statement:
http://goo.gl/mqpGG
Going to be interesting to see LightSquared present to GMDSS and NMEA folks next week!
They will push the Javad Ashjaee “solution” which, for only $300 to $800 per receiver, protects those receivers from interference!
http://www.amerisurv.com/content/view/9152/ >
The drawbacks are obvious and I can just see the military cramming these filters into their encrypted Blue Trackers. Do any of these guys have a practical bone in their bodies?
Interesting that Javad Ashjaee does not seem like a sock puppet for LightSquared or anyone else. His thinking is: “This is an engineering problem, not a legal problem. It should be called the Coalition to Save GPS and LightSquared, and the answer is staring us right in the face.” And he made a video to explain his solutions, link here:
http://www.amerisurv.com/content/view/8911/2/
Ignoring the soap opera for a moment. It appears to me that his solution will still require firmware updates to every GPS out there to deal with an unencrypted signal. Would L^2 be willing to provide vouchers to have this done by all affected GPS users?
In the tradition of the guy late to the party buys the bar, it seems L^2 should.
Chris, As I understand it LightSquared is on their third plan now and it does not threaten standard GPS. However, it would interfere with high precision GPS, which includes a lot fewer units though arguably some very critical units. The Javad solution is all about these high precision devices.
Ben,
Fair enough.
Having been part of shutting down SA, we found receiver firmware designs varied widely, and we got a lot of flack from some who accused us of having fiddled with the signal in the process of turning off the dithering. [We actually delayed planned changes so as not to change two things at once.]
When we investigated, we found several designers had used software to make up for hardware (antenna and front end) deficiencies/limitations.
So, it just seems the L^2 bar bill would be a smaller one.
Would like to see us get this behind us. Seems like there are more important things we could be dealing with.
C
Chris,
Are you saying that some manufacturers might be able to implement Javad Ashjaee’s “fence” in software?
Actually, the inverse.
First let me say I haven’t looked at processing code in a loooong time. But when I read the words “does not threaten standard GPS,” I just know that “standard” isn’t.
There are enough different implementations–parsing of processing between hardware and software–out there that I think we should expect there will be brand-bounded problems.
I have seven differently branded GPS units (fewer than you I am sure). One day I put them all as close together as I could. From an orbital dynamics perspective they were collocated. Lock-ons varied from 1 sec to 1 min. GDOPS were all over the place, and no unit was always better than the others.
I agree with the sentiment we would all benefit from both technologies being able to advance and prosper. I don’t think we have a technical handle on the situation until we have physically demonstrated we have.
C
Compromise?
It is not possible to bargain with a hijacker who doesn’t care about anyone or anything other than his own self-aggrandizing avarice. If “reason” were operating, this matter would have been still-born. It is purely about obtaining power and the usurpation of a public asset worth many billions of dollars converted for private gain.
As for willingness to compromise, one simply cannot “negotiate” with physics.
We are all merrily preaching to the Choir, here. What have you done lately to make a difference? Have you pestered your Senators and Representatives?
Did you write a comment to the FCC? Have you posted on any Newspaper sites? Do you have any other suggestions?
Remember: No Compromise Whatsoever with LightSquared is the goal, less they hammer a wedge into their “foot in the door” and convert public infrastructure into private profit center. Its been done before. Remember when NOAA would gladly give you a Gulf Stream Prediction? Try changing THAT back!
Christopher, my understanding is that precision GPS really is a different breed than the marine, car, and cell phone GPS most of us are familiar with. Specifically it uses spectrum well outside what “normal” GPS does, and that’s what conflicts with LightSquared’s latest plan.
Ben, I thought that they were more sensitive and had elaborate algorithms to average or correct readings the way that surveyor’s GPS units do. As I guess we all have seen, if you leave a GPS unit on in a fixed position with track on, you will end up with a solid dot surrounded by random tracks. The dot being the locus of readings after “x” hours. I’ve always thought that precision GPS had a way of accelerating the calculation of that locus or true position. I do know that early surveyor gear used a laptop to determine benchmark position after being lefdt out for hours.
The reason the military has a separate system is that they cannot afford that dilution of position. Military gear will have to be tested at White Sands as they are not going to turn their gear over to Lightsquared or anyone else.
Ben,
My understanding is the L1 carrier, 1575.42 mhz, feeds the L1 Signal, it is fed with C/A Code which has already been mixed with NAV System code.
The L2 carrier, 1227.6 mhz feeds the L2 signal. It is fed with P-code* which has already been mixed with NAV System code.
The output of P-code* can be fed both to the L2 signal and the L1.
I cannot say how many civil precise users are using L2 or not. In my day it was DOD/Intel/etc only. Since then it appears to have been (poorly) handled by export controls.
If the precision ag guys are doing precise positioning on the move, I would have to believe they are using L-2 P-code.
*When we turned off SA in ’94 on all systems, P-code was encrypted to Y-code. The suggestion that the military should turn off Y-code encryption is specious. Encryption, in this case, is not about preventing others from using the signal (ala SA), it is about reducing spoofing opportunities from pseudollites, etc.
Given I have friends and family in hostile places dependent on that encryption to put them where they are supposed to be rather than where a bad guy wants them to be, I’m dead set against turning off encryption. These suggestions always come from the $$ benefactors not the life risk takers.
C
So: now on top of Midair collisions, Train Wrecks, soil erosion, collisions and allisions at sea and on inland waters, LightSquared will kill our boys and girls overseas? Like the Salsa commercial; “somebody get a rope.”
The Lightsquared incompatibility issue, solutions, and impacts are confusing, might I suggest when we comment futher, we speak of the lower 10Mhz, vs. the upper 10Mhz? The solutions are different for the two (some would say no solution exists for the upper 10Mhz), the impacts are different (for some uses the lower 10Mhz may not have a solution either), etc.). E.g. “In regards to the lower 10Mhz, Lightsquare still has such and such issue, which impacts xxxxxxxxx” ). Just an idea.
How much bandwidth is 10Mhz or 20Mhz?
This (confusing) Verizon document gives some idea of what consumers receive in 10Mhz or 20Mhz of bandwidth with various protocols.
http://bookstore.ucsd.edu/images/pdf/VZW_LTE_Competitive_Comparison_Overview.pdf
To me, the answer depends on how many people are using it. See the Panbo article from yesterday.
In regards to the upper 10 Mhz, how long can Lightsquare go without the upper 10 Mhz? Will they be at a competitive disadvantage? (Not clear if they are, unless SPRINT is going to sell millions of iphones or droids that use it).
In regards to the lower 10Mhz, is the proposed Javad Ashjaee solution feasible? Who is still impacted with such a solution?
‘In regards to the lower 10Mhz, is the proposed Javad Ashjaee solution feasible? Who is still impacted with such a solution’?
I’d take that seriously. JAVAD is a respected provider of precision GPS receivers.
Lightsquared is running around telling everyone ‘I told you so. Interference is a simple engineering problem and we solved it’.
What problem did they solve? The original problem was GPS compatibility with both upper and lower LTE network channels. Now they say JAVAD will demonstrate compatibility with only the lower channel.
That’s kinda like Captain Kirk beating Kaboyashi Maru by reprogramming the parameters of the problem.
Then we still don’t know if GPS avionics can be fixed. Lower ten testing revealed a large differential in interference rejection between the best and worst performing equipments. That would imply superior front end designs do exist or, perhaps, robust processing algorithms can be implemented.
Additionally, some avionics tracked GPS signals but couldn’t acquire/reacquire signals while others experienced an unacceptable degradation of WAAS data integrity.
In reality, nobody knows what to redesign until FCC acts to reconfigure the Lightsquared spectrum for more compatibility with GPS weak signal reception.
Lightsquared cannot be too happy if they are restricted to the lower channel. As a first order approximation, I’d think users times speed product scales to the bandwidth available.
LTE networks provide six bits per hertz for 20dB signal to noise channels. That’s very good with respect to a theoretical (Shannon) limit.
— CHAS
Good ideas, Dan, and I tried to keep them in mind when I wrote the recent entry about “LightSquared vs GPS”, which is where readers of this thread should probably go for more info and further comments: http://goo.gl/M9Eh0
Interesting!
http://www.multichannel.com/article/478216-LightSquared_Commercial_GPS_Has_No_Right_to_Interference_Protection.php
This is a zombie thread but…
It appears that the FCC is doing an about face and on the Lightsquared proposal:
http://is.gd/tGqIwV
Facts can still trump marketing BS occasionally!
Charlie
Sprint bails out:
http://www.businessweek.com/news/2012-03-16/sprint-ends-partnership-with-billionaire-falcone-s-lightsquared
The final chapter:
http://www.forbes.com/sites/danielfisher/2012/04/04/falcone-seriously-considering-bankruptcy-for-lightsquared/
Ben, just in case you or other readers missed the news, the LightSquared fiasco isn’t really, really dead yet. Today, I saw this piece of news: http://news.yahoo.com/lightsquared-creditors-vote-latest-bankruptcy-exit-plan-191540020–sector.html
Apparently, the fight over the carcass is not yet done, and the discussions of “what to do about the spectrum” are continuing.
This problem has not gone away. In fact, the FCC recently granted the license. Lightsquared went through several reorganizations & bankruptcy, but the radio spectrum owned by the company was very valuable. Now known as Ligado, the company has lobbied the FCC and just got license approval. Originally, the radio spectrum was licensed to be used from satellites, which meant low signal strengths on earth, and negligible interference with GPS signals. Now the license has granted land-based transmitters, resulting in much larger signal strengths to terrestrial GPS receivers, and likely interference. Like digital TV, you either have GPS reception (position) or not (no position). And our government has yet to implement any system for backup PNT.
GPS World Magazine has been following the Lightsquared/Ligado odyssey over the years.
A recent article:
https://www.gpsworld.com/keep-gps-working-coalition-fights-fcc-ligado-decision/?utm_source=Navigate%21+Weekly+GNSS+News&utm_medium=Newsletter&utm_campaign=NCMCD200624003&oly_enc_id=3015B6621690D2W
UGH! Peter Janssen researched the politics behind this FCC decision and they’re not pretty:
https://cruisingodyssey.com/2020/06/30/new-fcc-decision-could-hurt-accuracy-of-gps/
But glad to see that BoatUS and many other reputable stakeholders are taking a strong stand.