Manic GPS

[tamaranth]

Just went for a run, yay! Week 5 of C25K: last time I did this was on the beach in Tenerife. It seemed a little easier. However, my GPS went completely haywire during the run and claimed I'd gone twice as far, twice as chaotically, as I actually had.




ABOVE, a fairly normal GPS track for one corner of the park.
BELOW, today's GPS track for the same corner.




So, what makes GPS go haywire?

Comments

[d-floorlandmine.livejournal.com]

Thats ... interesting! Were you in fact on fire? Or being pursued by a swarm of bees? Rounded up by a sheepdog with ADHD?

[tamaranth.livejournal.com]

none of the above, at least as far as I noticed! There were some small children but they were in a cage, or playground, or whatever the term is. Sunspots? Axial tilt? Will see if it happens cycling tomorrow.

[d-floorlandmine.livejournal.com]

Well, I did hear something about the quake in Japan having affected axial tilt a touch, though I didn't catch any details. And there was something a while back about solar flare activity, although I think that may have been a few weeks ago. Time ... passes.

Caged children shouldn't have too much of an effect on your route, unless they're actually some kind of Doctor Who monster affecting reality and/or electromagnetic frequencies.

[ivory-goddess.livejournal.com]

what makes GPS go haywire?

According to an article in New Scientist I read only this morning, jammers. Use by lorry drivers to avoid their location being tracked by their employers, or to stop being detected by cetain road tolls (mostly in the US I think), and also by practical jokers.

Mind you, I think jammers just blank them, rather thn make them think you've gone twice as far as you actually have.