On 5/19/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
I think you guys need to get this out asap. The only reason I do not buy the iphone right now is because it does not have GPS.
In the United States the iPhone, no doubt, makes use of radiolocation instead of GPS. Cingular uses Time difference of arrival (TDOA). This system uses multilateration, much like GPS. It is my understanding that civilian GPS is generally accurate within 15 meters. The FCC requires American cellular providers to be able to determine the position of a phone within 100 meters 67% of the time and 300 meters 95% of the time. It is my understanding that TDOA can currently achieve accuracy within 30 meters. Many modern phones support the Location API for J2ME (JSR 179). On a Cingular or T-Mobile network this location is provided by TDOA (unless your phone has GPS which it usually does not). I've used J2ME location based applications on Cingular's network to good effect. I have not been able to compare TDOA to GPS because I haven't had access to a GPS enabled phone. I think my question is why is everybody freaking out about the iPhone not having GPS? It will report location as close as 30 meters, usually within 100 meters and almost always within 300 meters. This accuracy is good enough for most applications. Even better cellular TDOA is accurate inside building as well as outside buildings (which in my experience GPS is not). Are location detection services like TruePosition's U-TDOA (used by Cingular and T-Mobile in the USA) not available internationally? So why is GPS the killer functionality the Neo has over the iPhone? (note: I understand why the OpenMoko development platform is better than the iPhone. I'm just talking about GPS vs. carrier provided location detection.) -- Andrew Becherer Undergraduate, Computing and Software Systems University of Washington, Tacoma _______________________________________________ OpenMoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community