Government turns up volume on GPS

The US government flicked the switch today on a new GPS signal, known as L2C. The signal, according to the government, is transmitted at a higher effective power, allowing it to "work better in urban areas and indoors." The new signal, being transmitted by the IIR satellite launched in September, can also be received using less power, potentially allowing better GPS reception by smaller devices such as cellphones. However, most current devices may not be able to make use of the new signals without upgrades.

[Via PhoneScoop]

[Jose Lara @ Jan 25th 2006 6:41PM]

hope my new blackberry has real-time gps now. no 10second lag time crap.

[Simon @ Jan 25th 2006 6:43PM]

This entry made it sound like just a single satellite is operating at this higher signal strenght, but any GPS device requires 4 signals from 4 different satellites. Perhaps L2C is a constellation of satellites and not just a single satellite, or perhaps it helps just marginally by providing at least 1 of 4 good, strong signals.
Anyone know for sure?

[furtim @ Jan 25th 2006 7:26PM]

It does sound like they're launching a whole new constellation of these. The linked article about the IIR launches says they're planning to roll out another seven of them, at least.

As for the specific nature of L2C, it seems to be an improved standard for the L2 frequency that's normally used for calculating ionospheric effects. So even if you only see one sat carrying the new L2C signal, you can still use it to correct for ionospheric distortions and improve overall accuracy. Up until the roll-out of L2C, this frequency has only been available to the military.

The main GPS signal is on the L1 frequency, so the new satellites don't really change how current single-frequency receivers work. Just they make dual-frequency receivers more useful for the public.

[Jeffrey Henderson @ Jan 25th 2006 7:27PM]

The reason this is happening is to make it easier for the govt. to track everyone. The FCC requires cell phone companies to have GPS in the phone. They say this is to help know where you are in an emergency but that's just a bunch of crap to get people to accept being tracked. Check out http://www.infowars.com to find out more about what the govt. wants to do to you.

Also, keep an eye on these sites. They're under construction but when they are launched they will raise the bar in their markets.

http://www.cigarexperience.com

http://www.adeptmarketingconcepts.com

Thanks,

Jeff

[Jeffrey Henderson @ Jan 25th 2006 7:49PM]

The links in my last post didn't work right, try these, http://www.cigarexperience.com and http://www.adeptmarketingconcepts.com

[Rick @ Jan 25th 2006 8:01PM]

You don't really need a new network. Just one satellite to pickup the signals from the existing satellites, and re-transmit their time signal on a single encoded, yet easier to pickup, frequency. So it could just be one satellite.

[SRD @ Jan 25th 2006 8:14PM]

Jeff are you a an idiot? You actually buy into all that crap, man that was good for a laugh people have to much time on their hands :)

[Martin Overstrom @ Jan 25th 2006 9:41PM]

GPSs alone cannot be used to track people. A GPS RECIEVER is exactly that, only a reciever. It simply recieves time signals from several satellites, and does math on the differences between them (due to the speed of the signal and the distances between you and the satellites) to determine your position.

[Matthias @ Jan 25th 2006 10:11PM]

Rick, a GPS receiver works out its position from the time it takes signals from four or more satellites to reach it. Retransmitting these signals from a single satellite would make them worthless for positioning.

[furtim @ Jan 25th 2006 10:55PM]

Rick: The single satellite has a limited footprint, so you still need more than one for global coverage. However, it's quite sufficient to have only one of the new satellites visible at a time.

As I described above, the L2C signal is used to characterise ionospheric condition and correct for the range distortion that the ionosphere introduces. The standard ranging stuff occurs on the L1 frequency, and you still need to receive at least four L1 frequencies in order to get a proper fix. If you can also receive an L2 signal, either because you've got the military's codes for it or because your receiver supports the new L2C signal, you can improve that fix by filtering out ionospheric distortions.

[Jimmie @ Jan 26th 2006 5:34AM]

The folks at Home Depot could use the GPS system to find their merchandise. Ask most employees where a product is and they can't tell you.What happened to training?

[Ian Jardine @ Jan 26th 2006 9:36AM]

Here's my understanding:
1) There are periodic software up[grades to all the Sats in place.
2) Hardware upgrades can ONLY take place as new Sats are launched, tested and put into use replacing units which end their useful life
Sounds like this new Sat is the forerunner for a series of new Sats to be launched and put into use over the next few years. This is important as new GPS ground nits can be modified to make use of the stronger, more accurate signal.
Conclusion: This is all part of the GPS systematic upgrade, which narrows the performance gap between the older GPS system in place and the intended (pay for most accurate use) Galileo performance advantage.