In my recent holyday in Denmark I had the opportunity to test the GPS module in a car. The last short test in a car produced a interesting behavior when we drove > 100 km/h. The module lost the fix and did not recover until vcar < 100 km/h. I assumed that this was because I chose the navigation setting 'pedestrian' because back then it was mainly used for hicking.
So with the setting changed to 'automotive' I gave it another test... and it worked flawlessly. The module never lost the fix for sppeds up to vcar = 130 km/h (Thats the speed limit on Danish highways). I even squeezed another 2 h of run time out of the same 18650 battery I used during my first tests. The total runtime now adds up to about 29.5 h!
To compare the position accuracy I recorded the track on the one hand with my trusty HTC One paired via bluetooth to the module and with my Xiaomi Mi Mix 2 (GNSS). The module as well as the mobile phone where positioned under the front window on the co-drivers side.
Comparing the tracks on the highway one sees virtually no difference (Xiaomi Mi Mix 2 in blue, GPS module in lime green). Both tracks almost superimpose along the ~54 km I recored.
In challenging situations where the GPS signal was weak or reflections disturb the correct positioning the module seems to drift less and recover faster. I assume this is because of the substantially larger antenna, so not a very fair comparison.
I put the GPX tracks of the highway and city test for both devices in the download section for everyone to compare.
All in all I am still very pleased with the device I build. The u-blox NEO M8N preformces awesome and this is without complex implementations and shilding.
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