Javad GPS May Save LightSquared's Bacon

 - October 4, 2011, 3:32 PM

Can GPS and LightSquared coexist? Within the civil and military GPS community, the answer has been emphatically and unequivocally, “No.” Until last week, that is. Attendees at the annual convention of the U.S. Institute of Navigation held in Portland, Ore., had been confident that the laws of physics made coexistence of the two impossible. So the announcement during the convention by LightSquared that, to solve the problem, it had teamed with Javad Inc.–a developer of precision GPS receivers–was met with both surprise and skepticism. Javad founder Javad Ashjaae, known as an outside-the-box innovator, is understood to have already developed proof-of-concept precision GPS prototypes that are unaffected by LightSquared’s 4G broadband transmissions. Further, production units are forecast to come out next year with estimated upgrade costs of $300 to $400 each. Since Javad has surprised the GPS industry before, most of those who previously criticized LightSquared’s plans due to GPS interference are reserving judgment until more details are forthcoming. However, the Coalition to Save Our GPS said that if the solution does indeed work, LightSquared should be required to foot the bill for the upgrades.


I'd take that seriously. JAVAD is a respected provider of precision GPS receivers.

Now 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. 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.

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.

The overall problem will not be solved overnight.

--- CHAS

LightSquared shuts down GPS receivers because the powerful signal (15,750 watts, or, maybe ½ that) just right near GPS receivers (up to many miles away) saturates the antenna amplifier in the GPS receiver trying to receive about 300 watts from about 11,000 miles away. No filter on LightSquared transmitters can prevent that. Need a filter on the GPS receiver after the patch before the gain stage to ground out the LightSquared off band signal. Here is ours: $1200 and the size of a brick and NOT a complete solution. Sanjiv Ahuja has said he has one for 30 cents. We are waiting to see one. Javad says they have a better GPS. We are waiting to see one. Either way, you all get to buy a new GPS.

Another way is to alter the LightSquared protocol, to contain "holes" that GPS can listen through. Doug Smith who is Chief Network Officer for LightSquared says "…I do not intend to follow up with you regarding your proposal" and "Please understand we have received hundreds of offers to solve our issue and simply do not have time to engage everyone." That option does not have you all buying a new GPS.

The reality of this situation is this. LightSquared pulled a fast one to acquire the spectrum at next to nothing in comparison to competitors. They smooth talked the FCC and the WH into giving them a waiver. Now they have sold BILLIONS in contracts and will threaten the FCC into giving them a pass. What will likely happen is a costly lawsuit which we the taxpayers will pay for and the FCC will ultimately move LightSquared into a different part of the spectrum, which was the ultimate goal from the start. I guess the hedge fund game works in the spectrum world as well as the collapse of the AMERICAN HOUSING MARKET, and Falcone wins again.

So we built a satellite based navigation system. The GPS receivers have changed the way we coordinate emergency responders, locate hazardous waste scattered during hurricanes, avoid getting lost on a trip and make possible military operations that were impossible without GPS.

This took years to design. We built rockets to launch the constellation. Tons of people have had a career working to improve the accuracy of GPS location.

GPS changed how we work and play.

How much money did it cost to create the working GPS we have now?
Currently the GNSS is being improved and will add L5 spectrum
- these changes will require new devices that could bring the cost of high accuracy location down to something reasonable. The planned budget for all this is quite spendy.

Lightsquared has delusions of grandeur, claiming that finding a legal loophole is exactly the same as changing the physics of our universe. They should have listened in high school science class because their ignorance is showing.

What do you think of this idea ?
1. Lightsquared broadband broadcast, if allowed, will damage the GPS system we use.

2. Damages have to be fixed; after my home run goes through your window, I have to pay to restore your window to it's undamaged state.

3. Lightsquared should not be permitted to damage businesses or public safety and national security that relies on receiving a clear GPS signal without any penalty.

4. Therefore, Lightsquared must pay for new GPS devices to replace all current GPS receivers that may be affected by their broadband wifi signal.


Will Lightsquared retrofit older GPS receivers with filters at no additional cost to the end consumer?

Of course not.

So, all those who already own a GPS receiver, whether it's installed in an airplane, a ship, a truck or a bus will have to either modify their equipment or purchase new equipment.

The total cost for those who depend on GPS for commercial, governmental or private use -- throughout the US and possibly along the Canada and Mexico borders -- will certainly exceed 100 million dollars.

Instead, Lightsquared should purchase a different frequency block and foot the bill. The entire country need NOT have to change to accommodate one stinkin' company. It should be the other way around.

I have over $50,000 invested in a GPS system (Trimble) for just one tractor. This system steers the tractor between the row crops and allows me to cultivate out weeds with precision instead of just spraying the whole field with herbicides and insecticides. If Lightsquared screws up this precision GPS it will cost me a ton. Hope you smart guys either come up with a solution or stomp Lightsquared until they move to another part of the spectrum that will not ruin my precision GPS. Thanks for all the help those working on this are giving us farmers...

There is only so much usable spectrum. Some of it better than other.
Personally I'd like a standard that fully uses the spectrum for public internet.

This reminds me of the people who were squatting in the white space only not quite as egregious.

All radio systems should be built so they can isolate and use only the desired bands without making other bands unusable to the point where we maximize usable communication spectrum. Technology will advance and some equipment will inevitably become obsolete. How long that period is, is open to reasonable debate.

Lightsquared is play dirty pool and should have to pay the public for the appropriate price for the spectrum in the intended use.

What seems like poor hardware design to me seems like an issue with the GPS manufactures being cheap stupid or lazy with regard to potentially interfering spectrum.

This spectrum was suppose to be kept "quiet" so what LightSquared is trying to do wouldn't happen. Was set up that way by US government with knowledge of all players. Nothing wrong with GPS receivers. They were designed to work with what was available and within the rules and they do. LightSquared wants to change the rules- which is what they are trying to do with the WAIVER- so that the rest of the world conforms to their rules.

All the arguments against L2 being able to use its designated L-band spectrum have merit, however most of the opposition appears to be predisposed to the fact that L2 got its spectrum on the cheap.

With demand for spectrum growing geometrically the need for opening up available spectrum should be a priority and if L2 can solve 99.5% of the interference to GPS, why then shouldn't they be able to use their spectrum. Nevertheless, L2 success will be conducive to the consumer as a whole in bringing much limited spectrum to the wireless industry and making the telecom industry much more competitive.

With L2 the smaller telcos will be able to compete with the likes of ATT and VZ, however without an alternative to the duopoly, ATT & VZ, the consumer is in for some major surprises.

Javad did nothing magical, several other GPS companies have demonstrated similar ability to filter the LS signal. Once the LS spectrum is put into the lower block, and a decision is made not to use services such as OmniStar and Starfire, filtering the LS signal is not too difficult. That is if you are building a new receiver or a special adapter. Of course, the problem is all the receivers deployed in the field, whose going to pay to fix those?

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