Disastrous GPS Jamming

As much as I hate to admit it, it's because it matches the majority of their constituency so well.

A satellite transmits its signal with bout 25 watts of radiated power. The proposed ground network will have transmitters using up to 1500 watts of radiated power.

Signal strength is reduced by the square of the distance between the transmitter and the receiver. You can now do the math.

http://gizmodo.com/#!5768148/4g-network-will-create-gps-dead-zones-across-the-us

I think this may have been discussed earlier but here's a new article on this.

Lightsquared just got additional funding. The article
http://www.cedmagazine.com/News/2011/02/LightSquared-UBS-JP-... has more details. To quote:

"LightSquared has closed $586 million in debt financing from UBS and JP Morgan, bringing its debt and equity financing over the past seven months to more than $2 billion."

The financial community is convinced this is going to happen. I hope we are not all too attached to our devices. I often said the 765T was probably the last standalone GPS I was going to buy figuring smarthones would be extremely capable by the time my 765T wore out. I did not consider the possibility that GPS itself might not be usable.

I kept my paper maps.

This one still has a ways to go. FAA/DOD aren't as easy to brush off, and don't respond well to "just upgrade your receivers..."

Precisely. There's just a wee bit more money involved than just spectrum.

Lightsquared is using L band frequencies to implement their LTE (4G) service, which happens to be very close to the frequencies used for GPS. Lightsquared's emitters/sources will be ground-based, so they will be stronger than the GPS signal being sent down from GPS satellites. Basically, Lightsquared's system is going to be "talking" a lot louder than the GPS satellites, thereby preventing good reception for GPS devices close to Lightsquared's emitters. So in this case, 4G is definitely going to interfere with certain GPS reception.

On the other hand, not all 4G systems are going to be implemented using L band (most LTE systems won't involve satellites like Lightsquared's evidently will), so your statement doesn't quite capture what is actually going on here. Rather, I would argue that it is only correct to say that Lightsquared's implementation of 4G will interfere with GPS.

Verizon's 4G/LTE will be in the 700mhz band.

All I can say is, I'm glad I'm normally no where near the US border if they're going to interfere with the GPS band signal.

And they call this progress?

Wait until we get it implemented and Industry Canada sees all the money the U.S. is getting from Lightsquared. To quote Bart Simpson, "They will fold faster than Superman on laundry day". Plus, GPS is a United States invention so if it gets jammed up here, other countries will take it as a green light to proceed with their own spectrum sell offs in that band.

http://news.yahoo.com/s/ap/20110406/ap_on_hi_te/us_tec_gps_t...

For the first paragraph, the agreement will be taxpayers will pickup the tab for new government equipment and owners of consumer grade "bricked" devices will pay for their own new equipment. It shuts up the FAA, DoD and other agencies that have issues with GPS jamming and allows us "citizens" to fend for ourselves.

The second paragraph pretty much sums up why it will get approved. The FCC wants it bad. They want to appear that they are solving the wireless competition issue, especially when they are going to approve the AT&T/T-Mobile merger in short order.

Again, the only ones who will suffer in all this are those of us who pay taxes and own GPS equipment. Everyone else is a winner which is why we all know it is getting built.

Remember FCC orchestrated the switch from analog to digital TV, taking away channels 52 and above and in the big cities restricting ch 14-20 for public sevice communication. The government paid $40 to everyone that needed a convertor box for their old TV. I doubt that the FCC will have a program for we GPS users.

You shouldn't equate the switch from analog to digital TV with the loss of GPS. The TV switch affected virtually everyone in the US of A. Of course the politicos had to make it look like they cared if they wanted to get re-elected. The loss of GPS will only affect users of GPS, you, me and the military. You and I don't carry enough weight for the politicos to worry about and they don't count the military vote anyway so they don't matter either.

It was nice while it lasted.

Problems with GPS affects a lot more than you think. The GPS satellites broadcast timing signals, not position information. Those timing signals are used virtually everywhere from your GPS to your cell phone, to the bank where you do ATM transactions. In 30 years the GPS timing has become an integral part of so much technology we use today that ANY disruption will be far felt.

I hate to disagree but none of the problems brought up so far are things that cannot be solved with lots of money. When I follow the money trail of winner and losers, there are too many "important" winners who will have a fit if this does not go forward:

1) Lightsquared: their project gets built and the Wall Street investment houses get paid back many times their $14 billion investment. They can certainly afford to grease a few palms in order to get approval.

2) Manufacturers of GPS devices: All the non-functioning devices, because of LightSquared interference, will need to be replaced and someone has to make and sell them. Auto manufacturers can sell replacement on-board navigation equipment and overcharge for them like they do now. A win for dealer service shops, electronics manufacturers and the auto manufacturers. Military users need DoD grade equipment and the defense contractors can make a mint selling and installing new GPS receivers. Public safety departments like police or fire will get new GPS equipment courtesy of taxpayer funding. The contractors that install that equipment in said vehicles will get paid very well to do the work. Garmin, Magellan and Tom Tom will do very well with people replacing their non-functioning equipment.

3) FCC: gets to loudly proclaim how they are fostering wireless competition by allowing another entrant into the wireless industry and providing cover to approve the AT&T/T-Mobile merger (they can claim there is no duopoly). Also they can point to the success of their nationwide broadband initiative by bringing in a nationwide broadband carrier available to rural areas.

The only "losers" in all this are people like me who will have to pony up for a new PND on our own dime because we do not get funding to replace our devices, pay higher fees to banks and such so they can replace their timing equipment, and pay the taxes to replace all the government hardware.

Everyone with power and connections wins with this. Plus I find this statement in the article rather disturbing and a good indication that the FCC will move forward:

If anything, it might open the GPS industry to a class action lawsuit but then again, the only winners will be the lawyers and the rest of us will get a coupon good for $5 off our choice of new GPS device.

My sentaments exactly

I guess all the present smartphones with GPS will have to replaced as well, as they'll be affected too.

This is getting more expensive by the minute...

BoxCar, when your timing/sync equipment cost is around $100k, an upgrade of $100-$200 is peanuts. And I'm not really sure that an upgrade is needed. The receivers probably already have the needed selectivity. After all your customer isn't going to be happy if the neighbor's cordless phone crashes his system.

This IS going to happen and there will be upgraded GPS receivers on sale soon. Get ready to shell out big bucks, both in equipment cost and taxes.

An eWeek story describes objections to LightSquared’s planned network in detail, saying that “the Obama Administration’s drive to approve wireless broadband could end up killing most GPS use in the United States.” The story mentions objections raised by the Departments of Defense and Transportation, as well as the Coalition to Save Our GPS. According to the report, the FCC will likely act in LightSquared’s favor but that ”GPS users will lose, and then ultimately so will the investors in LightSquared when at least part of the system is ordered shut down when the interference asserts itself.”

http://www.eweek.com/c/a/Enterprise-Networking/FCCs-Broadban...

Having lived just outside of D.C. all my life I've come to the realization that subliminal marketing DOES count. Anyone from the area has seen/heard countless TV & radio ads from military contractors, PACs, unions, and anyone else with an agenda to sell & the money to place the ads.

But to the point, I finally saw a local TV news segment about LightSquared & the potential GPS disruption. It was short & a bit shallow, but I was happy to see it covered. Maybe some progress? DOD seems to be fairly concerned about this it appears.

There's a huge amount of Congressional & other Govt. staffers in the area (the people that really set policy) and they all have a somewhat normal exposure to media here.

Keep sending in those cards, letters, & emails.

Possibly related to this thread:

"There's growing concern about a bill before Congress. The measure could reallocate radio frequencies to public safety agencies. That would essentially take away the frequencies used by the amateurs."

http://www.wfaa.com/news/local/congressional-bill-could-hamp...

The eWeek article lays out pretty well why the LightSquared project will go forward. Personally I do not have much faith in DoD's concerns. 1) The GPS jamming issue is a domestic problem not a worldwide problem. GPS will still work in Afghanistan, Iraq and all other countries outside the United States. 2) Equipment that does suffer from jamming will be replaced at taxpayers expense. It is not like the Generals, Admirals, support staff, etc. will have to dig into their own pockets to replace their GPS devices.

As for the article's comment that LightSquared investors could be losers if the network is ordered shutdown, do not for a minute believe that scenario will ever happen. Once that network is lit up and it starts carrying important traffic, it will be immortal as it too will be critical. This is one reason I see the FCC's rush to get it going. The faster it is built and activated, the harder it is for any opposition to gain a foothold. If it is activated this summer, it will be too late for Congressional action to stop it and by the fall, rural Congressman may be reluctant to shutdown the only service their districts have.

Personally I have no plans to replace my Nuvi 765T once it stops working. I have enjoyed using GPS in the car but if it becomes unusable, I am not planning to drop another couple of Benjamin's on yet another device that may very well get disabled by some other new project. I will give it to my sister in Canada, where they will not have any GPS interference and move on to something else.

If the fears of interference to the DoD receivers turns out to be a reality, the DoD will get LightSquared shut down immediately. It is a matter of national defense.

Now we have to remember that the DoD receivers are designed to be as resistant as possible to the potential jammers. We cannot be sure that the commercial receivers where 'profit is king' will be properly designed for the unexpected use of the adjacent frequencies. If it cost $.01 per unit to add in these 'unneeded' filters, then the commercial receiver companies are sure to have left the filter out to increase profits. This corporate greed and the later problems that it causes is not (and should not) be a problem for LightSquared. The proper recourse would be for a massive recall of all the defective receivers, forcing the original manufacturer to correct the design flaw. The FCC should act on our behalf (and LightSquared's behalf) and require this. My bet is that the FCC will cave and leave us to learn how to use paper maps.

if the interference does occur look for the DOD to get new frequencies and new equipment. Remember they deal with other peoples money, money is no object.

There are already L2 frequencies that DOD can use and there is a new civilian signal, L2C, on 1227.6 MHz (I suspect the existence of this signal will be one of the excuses the FCC will give to move forward - everybody buy new receivers that utilize L2C instead of L1C). The thing to remember is the GPS interference is a domestic U.S. issue only. Military and civilian GPS will continue to work in all other parts of the world, including Canada, where LightSquared is not in business as well as rural parts of the U.S. where LightSquared will not be putting up towers.

Also, I give little weight to the complaints by government agencies about GPS interference. They are fully indemnified by the taxpayers and any problems they have will be solved at taxpayer expense. As the previous poster noted, they deal with other peoples money so money is no object. This is really an issue for the non-government users of GPS and how little weight they carry with the FCC.

When the government gets finished with us in the next 12 months, we will have higher cell phone plan charges due to the acquisition of T-Mobile by AT&T and we will lose the use of our GPS receivers in urban and suburban areas.

A firmware update should do it?

I'm not going to lecture you on the profit motive (what you are calling "corporate greed") and it's relationship to your job but the first sentence in the above quote is partly wrong. The FCC requires new users to ensure that their use of the frequencies won't cause interference to existing, licensed users. It is LightSquared responsibility to prove that their equipment is operating correctly and meets all of the FCC's requirement/specs. Once they have done that, you are right in that their responsibility to correct the interference is at an end.

The second sentence is completely wrong. There is no basis for claiming a design defect/flaw. GPSs are operating correctly now and you can't hold a manufacturer responsible for changes in the equipment's operating environment. That would be like requiring Ford to retrofit ALL of the cars and trucks it manufactured to run on diesel because gasoline had became too expensive. But if the problem can be corrected by a software upgrade, then requiring the manufacturer to supply that upgrade free of charge would be logical.

When my 750 quits, it is going in the trash. I won't shell out another $500 + for another play-toy. I have up-to-date paper maps that are free.

That is a good question and only the manufacturers would know for sure. I am sure firmware could be developed for the GPS/DSP chipset to mitigate some of the interference but that would bring up two questions; 1) does the existing DSP processor have the horsepower necessary to take on the extra workload and 2) how much would the desensitization from LightSquared effect the overall reception. A software solution could perhaps reduce the amount of distance you need to be from the LightSquared transmitter before overall performance takes a hit. It could not eliminate it but where they are now reporting jamming detection at 3.57 miles (see http://www.gpsworld.com/gnss-system/news/data-shows-disastro...) that distance might be reduced to two miles (just picking a number out of thin air but I suspect they could reduce it to a number between where jamming is detecting and signal loss occurs).

Most likely the solution will involve a combination of improved DSP and a better bandpass filter that has an extremely sharp cutoff below 1559MHz. The sharper the cutoff (ie. the more square it looks on a plot), the more expensive the filter. In addition I can foresee manufacturers augmenting current L1 reception with the newer L2C and L5 signals which operate in the 1200MHz band, which is far away from LightSquared.

No, any licensee is responsible for any harmful interference caused by their system. The rules state one user may not cause harmful interference to another. There is no time limit on when between when the interference is reported and the interferer having to correct the problem.

EDIT: The question of who is the interferer is partially answered by the date the license was issued. The first user licensed has the primary right to the frequency and anyone coming afterward is responsible for correcting problems the first user experiences, but must accept any interference received. In this case, the primary user of the frequency is the Federal Government and Lightsquared, whose license came later must correct any interference they cause. (And yes, the Feds are issued "licenses" but not by the FCC.)

Requiring manufacturers to correct a problem that is not of their making, in this particular instance, seeing if a software patch (it won't by the way) fix the problem becomes an unfunded federal mandate - and those can be legally challenged. Don't look for the manufacturers to retrofit their systems for free. That's the reason the waiver is being fought by so many manufacturers.

Lets be honest about that $40. They never paid people $40. They ran a disorganized coupon program that cost millions in extra overhead to give consumers coupons. The coupons could only be redeemed by big business. The consumers who bought adapters saw adapters on the shelf that sold at higher prices, but were supposedly "cheap" after the coupon. but in reality the coupon inflated the actual price of the device.

At the same time that you could buy a little converter box of electronics that outputted video signals in old NTSC standard 480i quality for $49-$59 or more, you could also buy a similar size DVD player that has electronics and mechanical hardware (the DVD mechanism complete with laser), that could output in NTSC and also higher quality comonent output and sometimes even HDMI or DVI for $29 or less. In reality if there were not coupons, the digital receivers would have been far less expensive, and more competitive on features (adapters actually were excluded from the coupon program if they had features beyond a minimal list, which makes no sense from a consumer viewpoint but certainly helps big business who wanted in on the coupon boondoggel).

Both of my nuvi's have a jack for an external antenna. If this LightSquared network causes interference with our existing GPS devices (as many of you are predicting that it will) is it possible that an external antenna with more precise signal filterng could be added to these devices that would make them usable again? I don't understand the technology well enough to know if that is a stupid question, but thought some of the experts here would know.

Also, it would seem to me that the major PND manufacturers like Garmin and TomTom would be doing some intense research and design planning for new models that will be able to operate without interference from the LightSquared network. I wonder if there are any new products like this on the drawing board that will be announced any time soon. I would like to get a new nuvi, but I think I will just live with what I have until the full scope of this issue is clearer.

Is this a local or national issue?

It is a national issue in urban and suburban areas where LightSquared intends to install terrestrial transmitters. In rural areas, they intend to augment their network with satellites. In those areas there will not be any terrestrial transmitters so no interference problems. This is basically why DOD is good to go outside the United States. GPS will not be effected in Europe, Afghanistan, Iraq, Libya or any of the other hotspots we are deployed to.

Boxcar wrote:

The FCC is not involved in policing interference. They will record your complaint, but are not required to act upon it. Furthermore, Lightsource would be interfering with a GPS system owned by the government, not Garmin or TomTom. We users of the system are not the licensee.
If our current devices become unusable in large cities, I'm sure that Garmin would be happy to sell us a new model, perhaps even giving us a trade-in on our old ones.

I'm not sure what you assume my job is, as I never stated it. Putting that aside, you also call out my statement of a defective design on the GPS receivers. I am making the assumption that the LightSquared system will be properly designed to not bleed over into the GPS frequencies. Every article that I have read on the subject raises the fear that the civilian GPS receivers might not be able to cope with signal on the adjacent frequencies. The articles state that it is trivial to filter these frequencies, but the receiver manufacturers never had to concern themselves with it for now.

If there turns out to be interference, there are two possible scenarios:

1) LightSquared is bleeding over into the GPS frequencies. If this is the case, LightSquared will be shut down until the bleed over can be corrected.

2) LightSquared is not bleeding over into the GPS frequencies, but poorly designed GPS receiver front ends are failing to filter out the non GPS frequencies. If this is the case, then the defective GPS receivers will remain nonfunctional until their design flaw is fixed.
Yes, it is probably a pipe dream to hope that the GPS manufacturers would correct their design flaw in existing fielded products. It would probably take some court action that would only make the lawyers richer, and everyone in the US would get a $1 settlement to share.

My real point is that is a whole lot of worrying over mostly nothing. The media, who don't really understand the issues fan the flames of hysteria to increase ratings. Then we all act like cattle. If there is a real problem with LightSquared it will be fixed, or LightSquared will be shut down. More likely, design flaws of the cheaper GPS receivers will expose themselves and the greedy manufacturers will blame LightSquared while they try to sell us their new and improved model that does what the original should have already done.

Before you get too far down the path of the FCC not policing interference, take a look at: http://www.fcc.gov/eb/

What isn't in their headlines are the actions they have taken against people causing interference and using unlicensed radios. The EB or Enforcement Bureau isn't the tiger it used to be as over the past 15 years it has lost personnel charged with investigating and enforcing interference complaints so more lawyers could be hired to write regulations.

The Bureau began to change from a technical bureau to an administrative agency under Clinton. Engineers were replaced with lawyers and technical departments shrank as they couldn't get replacements.

So yes, in some ways you are right in that the FCC isn't as active in enforcement, but its due to a lack of personnel more than a lack of ability. I think they have gone down to about 8 field offices from over 20.

I would not even consider this a design flaw. At the time of design, there were little to no close, adjacent frequencies in use. Moderate filtering would have been completely adequate for proper operation. The closer two frequencies are to each other, the harder it gets to filter one of them out. This is not really a retrofit possibility, it will be a "buy a new one" correction. Actually, an external antenna with additional notch filtering in it's amplifier section might 'fix' your older GPS. The question becomes, would it make sense to spend $50+ to 'fix' your older GPS?

I have heard from folks across the country and it seems this may only be the beginning. One side was military training on the west coast to the coming of 4g phone upgrades.

Time will tell what will happen and to what extent it will affect each of us.

http://www.wirelessweek.com/News/2011/04/Policy-and-Industry...

A bunch of senators want the FCC to put Lightsquared's deployment on hold until they can DEMONSTRATE no interference to GPS.

Lightsquared's regulatory compliance guy made the helpful suggestion that GPS receivers made after 2003 should have been designed better -- real helpful!

His statement that units which misbehave are doing so because they weren't designed well enough seems like a left-handed admission that they know their system screws up GPS something fierce...

I'd say things are starting to get interesting!

Lightsquared represents A LOT of money. They are gonna get what they want. The congress critters squealing is just politics as usual. They can now go back and say, "Well, we tried but we just couldn't save your GPS service as it exists now." I used to think that if we could just get rid of them and put new people in their place we could fix congress. But it can't be fixed, we've put new people in twice in the last 20 years and it's worse now than before.

Use your GPS now while it still works and enjoy it.

write to your Congresscritters and let them know how you feel:

http://www.usa.gov/Contact/Elected.shtml

this website makes it easy, very easy!

Regards, Ted

This is one of those issues where the Left and the Right...Conservatives and Liberals...Democrats and Republicans can all make a difference together. Unlike guns or abortion or health insurance this is a concern to everyone that has laid down their hard earned cash (or welfare payments for that matter) on a GPSr...the kind of pressure that can be put on the sleazeballs in DC is enormous when it is impossible to play us off against each other.

Write and write again...don't let them off the hook...

/rant

I just use my cellphone for GPS navigation. I have a 765t, which I havent turned on in months now. My phone has updated, more accurate info, so, I seriously do not care about Garmens interference. As long as my cellphone works, that is all I care about!!

Pay attention - if your cell phone tower can't receive a GPS signal, it can't connect a cell phone. The satellites don't broadcast position, they broadcast a timing signal. It's the timing signal that gets interfered with, and if that goes away everything timed off it also goes away.

If you use the GPS function only (no network location function), it will be interfered with as well.

May be light squared system should be made better I say GPS are first.I also think they shouldn't be trying to do a slick move and get their system approved before any one knows about it.Doesn't sound like light squared is going to be any help getting this problem resolved.I wrote my state senators,lets all get on the band wagon.

Are you saying that Ford should recall all of the Model T and Model A's they produced and bring them up to today's standards? Designing a product for today's market that works properly is the responsibility of the manufacturer. Once he has met that responsibility he is done with the model. It isn't his fault if the operating environment of the device changes. That would be like buying a light jacket in September and expecting the manufacturer to upgrade your jacket to a car-coat in January when the weather turns cold.