Nokia offers assistance for unresponsive GPS phones Nokia has tacitly admitted the GPS units it builds into a small number of its mobile phones are having problems quickly calculating their locations and has fallen back on data sent over the mobile phone network to mitigate the issue. But wait a minute - it's not a bug, it's a feature. Nokia is spinning the approach as a "new …
I've tried out 2 Orange SPV M700s, the models with a Magellan GPS device. They were ok in getting a 2D lock, but both are crap when calculating elevation, consistently reporting a figure about 60m too high.
Fine for SatNav, but no good with MemoryMap: When mountain climbing, it's worse than useless.
The T-Mobile equivilant, with a Sirf3 GPS, is much better
Please note, this is not DGPS, nor will it ever have that kind of accuracy. In fact, a questionable initial fix will make things worse, not better. I'd almost say that this is "we cocked up GPS. Here's a work around that we'll be calling a feature. Good luck and God speed. And whatever you do, don't make a left turn in the middle of that bridge."
The delay in initial GPS lock is because the GPS receiver has to receive an almanac from the satellite that tells the GPS receiver where every satellite should be at any given time. A-GPS simply provides the almanac via an alternative method meaning that the GPS receiver in the phone can get a proper fix much more quickly. That's why GPS receivers re-acquisition time is always much quicker than initial acquisition.
Correct this is not Differential GPS, it DOES have the potential though.
IF nokia's server was in contact with fixed position reference GPSs and forwarded the relevent corrective data to the phone, you'd have a slightly lagged, but still perfectly valid DGPS system.
Initially locating a GPS receiver through another tracking system is hardly new, a quick google finds a number of references tieing it to INS dating back over the last decade.
This is a case of a company actually using one feature of their product to enhance another, thereby getting the most "bang" from the available components, most people would call that "Good Engineering"
Anyone who knows anything about GPS knows that at heart it falls into downshift/demodulation,timing and then common or garden number crunching. Once the RF and timing exercises are accomplished it doesn't matter if the number crunching is performed by a dedicated DSP or as a process in the phone's OS.
... how it works.
I just updated my N95 software after reading this and I'm impressed. The built-in GPS now seems as responsive as the bluetooth sirf receiver I have. It managed to pick up a position indoors, which it wouldn't do before, so outside I expect it will be even better.
This, and the release of Mail For Exchange support for N95 is restoring my faith in the device, and Nokia.
All I need now is for tomtom to pull their finger out and issue an update for TT Mobile.
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