On Monday 05 December 2011, Dr. H. Nikolaus Schaller wrote: > Hi, > > Am 05.12.2011 um 15:51 schrieb rakshat hooja: > > On Mon, Dec 5, 2011 at 2:44 PM, Dr. H. Nikolaus Schaller > > <[email protected]> wrote: We have seen that the N95 has a quite simple > > flexible PCB GPS antenna instead of the ceramic > > patch of the GTA0*. Does anyone of you own > > both, a N95 and GTA0*? > > > > > > I have a N95 and a few GTA02s. Let me know what exactly do you want me to > > test re GPS? > > Great! > > Do you have some software for both that shows the > satellite positions and (relative) signal strength? > > What will be interesting is if the GTA02 sees the satellites > more uniform. > > The background is that the ceramic patch antenna in the > GTA02/04 should have a more omnidirectional sensitivity > while the N95 has just one flexible PCB with a long wire.
?! Would that actually provide enough signal to get a lock without assistance? I ask partly because it may explain why a friend couldn't get a gps lock on an N95 when on deck on a yacht out of range of mobile networks. GTA02 was reliably coldstarting in ~40s as you'd expect with a clear sky view like that. You need significantly better signal to get the initial fix than to maintain it, as we found with the SD drive strength issue. > And the latter should show some clear direction sensitivity. > > I.e. if the device is rotated some satellites should > become weaker and others stronger. > > So far the theory we want to probe :) > > If the N95 antenna does not show such effects, we > may have a cheaper approach for future GTA04 variants. > And they may be more easily integrated into new cases > than the 15x15mm ceramic block... Have you looked at an antenna like this? Smaller, cheaper and lower performance than a patch antenna, but probably significantly better than a wire. https://www.sparkfun.com/products/9131 > Many thanks for any results, > Nikolaus _______________________________________________ Openmoko community mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/community
