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Tips and questions relating to the GPS modules from SFE
By bilgun
hi. i want to improve the quality of gps of gm862-gps. because every time i when i receive the coordinate info they are all different from before and its far away from where i am(i got my coordinate from google map).
i can get the coordinate with
and repsonses are
$GPSACP: 074034.999,4754.9335N,10652.4831E,3.2,1372.7,2,27.25,0.28,0.15,011108,0

$GPSACP: 075648.999,4754.9187N,10652.4415E,2.4,1457.9,2,148.69,0.50,0.27,011108,


and my coordinate which i got from google map is

so what should i do. may be is it because i'm in my apartment(next to window)? do i have to receive outside?
User avatar
By leon_heller
Try it outside.

You might have a problem with the antenna, I don't have any problems with the similar GE-863 indoors.

By maokh
You are lucky that GPS receivers these days even work inside! ;)

If indoor operation is required, you can also try to average fixes to potentially gain higher accuracy.
User avatar
By leon_heller
I am on the top floor, which helps. 8-)

By olivier_p
The coordinates are probably not in the same format

From your gps, 4754.9187N is probably in the format 47 degrees and 54.9187 minutes North

From google, 475455.0908 is probably in the format 47 degrees, 54 minutes and 55.0908 seconds.

55.0908/60 = 0.91818 minutes which is very close to the 0.9187 from your receiver
By TomasTrek
I always find with my GM862 that even when the device is stationary the location reported by the device jumps around, usually in a predictable pattern and in a radius of about 60-70 metres from where it actually is. When the device is on the move the accuracy is pin-point though. Id have thought it would be the other way around, but apparently not.

You can put the devices coordinates into the search box in google maps, but you need to space it out a little. Just remember to try split the numbers before the decimal into groups of 2 (and if they dont go, the longest group at the start), then itll work in GMaps. Like this: "47 54.9335 N,106 52.4831 E". Put that in google maps and itll take you here: ... iwloc=addr

If you do the same to your location that you posted up as reported from google maps (47 54 55.0908 N 106 52 33.902 E) it takes you here: ... iwloc=addr which is pretty close, especially considering youre running it indoors.

(after following the links, the search box should be filled in, so click search otherwise for some reason it doesnt show you the point marker)

You can manually convert your coordinates to DEGMIN (what is used in the google maps api) by dividing it by 100 then dividing the right side of the decimal by 60.

Heres some simple php code I use to convert it:
Code: Select all
$coord /= 100;
$p = explode( '.', $coord );
$deg = $p[0];
$min = $p[1];
$min /= 60;
$min = round($min);
$deg .= '.'.$min;
$coord = $deg;