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@movq Indeed, that's terrible! Back in the days when my mate recorded the bike tours, we noticed that sometimes the reception was really poor. Whenever it took about three to five minutes or so until the location was found, we knew, the GPX is not going to be great that day. Sometimes there was a jump of several kilometers right after starting the track when we couldn't be bothered to wait for enough satellite contact. Our top speed was astronomically high. :-D
@lyse *Kilometers*? Never saw that, luckily. 😅 Seems like you were going at https://www.youtube.com/watch?v=HiO0SdAxMw4
@lyse *Kilometers*? Never saw that, luckily. 😅 Seems like you were going at https://www.youtube.com/watch?v=HiO0SdAxMw4
@lyse *Kilometers*? Never saw that, luckily. 😅 Seems like you were going at https://www.youtube.com/watch?v=HiO0SdAxMw4
@movq Yeah, basically it took the last known point from whenever that was (some hours ago when the phone had GPS reception) and then jumped to the real location, once that was known. That's why we travelled highspeed. :-) On bad days the accuracy was off by at most 40-50 meters I'd say. Usually it was relatively close to reality, in the range of 2-15 meters.
@lyse Ah, as I “learned” (more or less, I haven’t grasped it all yet) from the course I linked a few days ago, this appears to be a normal thing to do for GPS receivers. If they don’t assume some position, then they can’t solve a non-linear set of equations. (Something along these lines. I should probably get The Book on GPS. 🤔)

I would assume that more sophisticated receivers just do a better job at hiding this from the users these days. 🤔
@lyse Ah, as I “learned” (more or less, I haven’t grasped it all yet) from the course I linked a few days ago, this appears to be a normal thing to do for GPS receivers. If they don’t assume some position, then they can’t solve a non-linear set of equations. (Something along these lines. I should probably get The Book on GPS. 🤔)

I would assume that more sophisticated receivers just do a better job at hiding this from the users these days. 🤔
@lyse Ah, as I “learned” (more or less, I haven’t grasped it all yet) from the course I linked a few days ago, this appears to be a normal thing to do for GPS receivers. If they don’t assume some position, then they can’t solve a non-linear set of equations. (Something along these lines. I should probably get The Book on GPS. 🤔)

I would assume that more sophisticated receivers just do a better job at hiding this from the users these days. 🤔
@movq Ah, that's interesting! In my mind it even makes perfectly sense to just assume the last known position in lots of scenarios. The user might just be still (roughly) at the same location before the device was turned off. What alternative does the GPS tracking application have when a track should be recorded? Refusing to start the tracking until GPS signals are received isn't very user-friendly either. Usually, we waited until the location was figured out, so that the resulting GPX was somewhat reasonable. But sometimes we just began our tour while the device was still calculating the current position. And then we went supersonic. :-D
@lyse Yup, the only alternative is currently “Assisted GPS” and that requires an internet connection. (That gives you almost instant access to satellite data; instead of having to download it from the satellites directly at their super slow 50 bits per second.)
@lyse Yup, the only alternative is currently “Assisted GPS” and that requires an internet connection. (That gives you almost instant access to satellite data; instead of having to download it from the satellites directly at their super slow 50 bits per second.)
@lyse Yup, the only alternative is currently “Assisted GPS” and that requires an internet connection. (That gives you almost instant access to satellite data; instead of having to download it from the satellites directly at their super slow 50 bits per second.)
@movq Oh, I didn't know that!
@lyse Thinking about it, I have no idea how the GPS in my car can get a fix so quickly. 🤔 It doesn’t have an internet connection, at least not that I know of. It *should* take several minutes for it to get a fix. The only thing I can think of is that it regularly downloads the satellite positions from the satellites – in the background, even when the car is just parked here and is “turned off”. 🤔
@lyse Thinking about it, I have no idea how the GPS in my car can get a fix so quickly. 🤔 It doesn’t have an internet connection, at least not that I know of. It *should* take several minutes for it to get a fix. The only thing I can think of is that it regularly downloads the satellite positions from the satellites – in the background, even when the car is just parked here and is “turned off”. 🤔
@lyse Thinking about it, I have no idea how the GPS in my car can get a fix so quickly. 🤔 It doesn’t have an internet connection, at least not that I know of. It *should* take several minutes for it to get a fix. The only thing I can think of is that it regularly downloads the satellite positions from the satellites – in the background, even when the car is just parked here and is “turned off”. 🤔
@movq Good question. Probably exactly as you described it.