LightSquared's Threat To GPS looks Dead!

I told ya'll it wouldn't happen.

LightSquared's Demise

This is really good news. I am glad to be one of the people who called my representatives and wrote the FCC to oppose this very bad idea.

In the way of legislation, nothing is dead until it's stayed dead a long while.

Kind of like a campfire. You have to pour water on it, stir the ashes, and feel with your hands to be completely sure.
And even then you can't be totally sure.

I did some looking around about the lightsquared issue last week, and the more I read about it, the more obvious it was never going to happen.

For those who hadn't seen many details (most news articles didn't have the relevant facts), I'll summarize.

Lightsquared bought a chunk of spectrum from a 3rd party that was intended for satellite to earth transmission(licensed as such, ie that was the only permitted use for that spectrum). They then wanted to use it for terrestrial transmission. The FCC said, we will allow you to do this, IF and ONLY IF you can prove there will be no interference to any GPS devices. Which they obviously haven't been able to do, which is why they're proposal is being rejected.

As for the specifics, anybody who isn't familiar with electronics design, basically it comes down to the filters used to listen to a specific part of the rf spectrum. Its impossible to listen to only an exact chunk of spectrum, without hearing anything on the other sides. Filters have a rolloff on either side where the amount of signal passed through approaches zero. Same thing with regards to transmission, you're going to bleed slightly beyond your spectrum. This is the reason that satellite spectrum ranges are contiguous, without terrestrial transmissions right next to them. The power used by terrestrial transmission is (if I remember right) somewhere around a billion times more powerful than that of satellite to earth transmission. It isn't practical to use the type of filters necessary to filter this kind of noise (they'd be huge). Which is why the spectrum in question was never licensed for terrestrial transmission.

Good explanation!

Lightsquared doesn't appear to be the brightest company. Throwing money into buying this spectrum and planning to use it for something other than what it is reserved for. They probably figured they have more money than politicians have sense. Wait, that's probably a true statement. But Lightsquared ended up losing anyway.

There was one comment I found where it was estimated that the $2 billion worth of spectrum they bought would be worth around $12 billion if they had gotten their way (who knows how accurate those figures are). Still not a smart gamble, but maybe they thought their propaganda machine would manage to convince everybody.

They thought they had the political juice to muscle it through and make GPS manufacturers and users bear the cost of supporting their business plan. I'm actually surprised that it didn't work.

I wonder if LightSquared could have incorporated a GPS-like signal into their spectrum so that rather than interfering they would have enhanced the GPS system. Garmin, Magellan, Trimble, Tom Tom, et al would have needed to redesign their receivers, but I'm sure LightSquared could have helped with that considering the payoff if LightSquared's system could have been made to work.

I guess we'll never know.

If I needed to use GPS for some mission critical application, like the precision positioning of a surveyor or the precision timing of a scientist or any number of other applications, I doubt that I would put my trust into an alternative GPS signal from a company that is degrading the original GPS signal in the first place.

Nope, won't work. The way GPS works (really simply) is all the satellites have atomic clocks on them, and broadcast their time. The receivers are using the differences in time from the satellites to figure out how far it is from each of them. Trying to relay the signal changes the timing of all of that and wouldn't work.

The really big push-back came from mobile wireless providers themselves. ALL of their timing is GPS based (revenue and all that), plus the e911 location services use GPS and triangulation. Additionally, the multiple access architecture needs the timing accuracy of the atomic clocks in GPS.

Just try screwing with (Insert Carrier Name Here)'s revenue stream AND compete against them at the same time. It is a damn wonder Falcone didn't go on vacation to see Jimmy Hoffa.

My suspicion is that the competitors were who really killed this off. It may well have needed to die anyway, but the guys with money on the line have the clout.