Is it true that satellite lock is faster in Winter than Summer?

[jlh96]

I've noticed that it now takes about 1-2 mins before takeoff to obtain 15-18 satellites. Before, it would take about 30 seconds. I posted this question in the DJI Mavic Air facebook forum and somebody said that satellites are acquired faster in the winter than summer and also trees growing leaves. I am flying in an open area so I don't know about the trees, but is there any truth behind the season? Maybe sun angle and amount of solar radiation??

 

[pross]

Sounds like a load of **** to me, if that was the case there would be warnings about driving in winter because of the satellites lol.

 

[Meta4]

I've noticed that it now takes about 1-2 mins before takeoff to obtain 15-18 satellites. Before, it would take about 30 seconds. I posted this question in the DJI Mavic Air facebook forum and somebody said that satellites are acquired faster in the winter than summer and also trees growing leaves. I am flying in an open area so I don't know about the trees, but is there any truth behind the season? Maybe sun angle and amount of solar radiation??

Sun angle and solar radiation would have no effect and where the satellites are, there's no summer or winter.
I suspect that more testing would show that the acquisition time just varies regardless of the season.

 

[sar104]

I've noticed that it now takes about 1-2 mins before takeoff to obtain 15-18 satellites. Before, it would take about 30 seconds. I posted this question in the DJI Mavic Air facebook forum and somebody said that satellites are acquired faster in the winter than summer and also trees growing leaves. I am flying in an open area so I don't know about the trees, but is there any truth behind the season? Maybe sun angle and amount of solar radiation??

If it were affected by the angle of the sun then it would also vary by time of day.

 

[ac0j]

Radio propagation can be affected by many things. Solar flares, cosmic dust etc. Not really a season thing but more of a random occurrence.

Edit to add, any delays would be minimal at best.

 

[nica]

Actually the GNSS is affected by the solar cycle, but right now we are in a period when the activity is getting lower til 2020. It was much worse some 5-6years ago. Right now I don't think it has much effect on the receivers.


During the day the quality of GNSS is changing depending on the configuration of the satellites. In some areas you can encounter problems around noon when usually most of the satellites are low.
I had problems when measuring with a standard GNSS rover, never had these problems with a drone, but I guess the receiver in the drone is affected the same way.

 

[Meta4]

It's probably a good idea for the OP to do some more observation to see if there really is an issue rather than assuming based on a small number of observations.

Actually the GNSS is affected by the solar cycle, but right now we are in a period when the activity is getting lower til 2020. ... Right now I don't think it has much effect on the receivers.
Solar activity doesn't have a strong enough effect to make any practical difference.
During the day the quality of GNSS is changing depending on the configuration of the satellites. In some areas you can encounter problems around noon when usually most of the satellites are low.

The orbits of the GPS satellites mean there are always sats visible in your sky and there's no time when numbers are low.
Here's an animation to illustrate the orbital motion ... and there are more sats now + all the Russian Glonass sats as well.

 

[tcope]

First, I saw no support for what was claimed (winter and tree leaves). What I found, I'm not 100% applies here but it seems that the GPS sats send updated info that the receiver uses too acquire a lock more quickly. Perhaps if you are flying less during winter, it takes longer to get a lock as this information is allowed to get stale and needs to be updated each time. Again, I'm not sure this is correct.

 

[Meta4]

I'm not 100% applies here but it seems that the GPS sats send updated info that the receiver uses too acquire a lock more quickly.

Good point .... that is correct.

Time to first fix - Wikipedia

en.wikipedia.org

 

[Rayray]

Radio propagation can be affected by many things. Solar flares, cosmic dust etc. Not really a season thing but more of a random occurrence.

Edit to add, any delays would be minimal at best.

Being an Amateur Radio OP, I agree. Plus, in the case of GPS Sats, the grouping and other daily variations contribute. As most of us know, GPS Sats are not stationary. Finally, for any first flight of the day, acquisition will be MUCH slower than for subsequent flights.