Hi... How long does it take for your M3 To get GPS locked?

Sorry mate, I assumed you asked me to create the poll which means mine is a duplicate.

Suren Posted at 2-15 00:05
Sorry mate, I assumed you asked me to create the poll which means mine is a duplicate.

No Worries... I initially didnt know If I qualify to create a Poll...
All good.

... it is really very difficult to make a "more precise" statement on this! As soon as there are some trees or structures nearby, it takes up to 6 or 7 minutes... In an open field maybe only 2 - 3 minutes... And then it obviously also depends on the cloud cover. With a clear sky it "felt" a little faster than with dense clouds... Nevertheless, my tip (I picked it up from other users and it makes the most sense to me): First switch on the Mavic 3 and then get the other components ready... It probably makes the wait feel a little shorter. As soon as the HP message comes, I always start vertically upwards and stay for a few seconds (approx. 5 - 10 s) at a height of approx. 6 - 7 meters. The return to HP is then so precise that it really surprises me! I use a (colored) landing pad and the landing is absolutely perfect. Every time!!! As you can see: Germany Software as of January 24th

Yes.. I do Agree I always Switch on the Drone first before I connect the Phone and RC...

Too many threads on this topic now. why are we making so many threads on the same exact issue? Admins should consolidate it down to one thread.

US, Colorado.  As others have mentioned, if I stay earth bound and in an area with obstructions to the sky, this is higher.  If I fly up when I have "app permission" for 30m, this shrinks down to the 1m-3m range.

frankymusik Posted at 2-15 06:23

And then it obviously also depends on the cloud cover.
Obviously?

GPS reception is not affected by cloud cover

Well, unless the clouds are actually volcanic ash.....Mt Sain Helens anyone?

Labroides Posted at 2-15 13:12
And then it obviously also depends on the cloud cover.
Obviously?

... I can't believe it (yet).
Electromagnetic waves can also be weakened by moisture (rain clouds?), right?
A little bit at least?
And if the GPS module reacts very sensitively here, with the Mavic 3...?   

frankymusik Posted at 2-17 00:40
... I can't believe it (yet).
Electromagnetic waves can also be weakened by moisture (rain clouds?), right?
A little bit at least?

Really ??
It would be a pretty poor navigation system if planes and ships couldn't tell where they were in rain or overcast.
GPS was designed to be an all-weather navigation system and it works.
Clouds don't affect it.

http://gpsinformation.net/gpsclouds.htm

I have 3 flights right after the snowfall. And I am adamant: For these flights, the GPS lock time was up to 2 times slower than other flights to the same places at other times. On the other hand, clouds during beautiful sunsets do not have any significant effect.

So the type of cloud affects the attenuation of the signal. There is always a fading. On every signal and in every environment. It may be small or large, but it is there. Well-designed systems are no problem because they are designed for the worst case scenario. They have a big reserve .The bad times of the GPS lock on МAVIC 3 indicate insufficient reserve.

KokoFresha Posted at 2-17 02:35
I have 3 flights right after the snowfall. And I am adamant: For these flights, the GPS lock time was up to 2 times slower than other flights to the same places at other times. On the other hand, clouds during beautiful sunsets do not have any significant effect.

So the type of cloud affects the attenuation of the signal. There is always a fading. On every signal and in every environment. It may be small or large, but it is there. Well-designed systems are no problem because they are designed for the worst case scenario. They have a big reserve .The bad times of the GPS lock on МAVIC 3 indicate insufficient reserve.

So the type of cloud affects the attenuation of the signal.
Cloud has no effect that you could measure.
If it did, GPS wouldn't be fit for its intended purpose.

Labroides Posted at 2-17 03:10
So the type of cloud affects the attenuation of the signal.
Cloud has no effect that you could measure.
If it did, GPS wouldn't be fit for its intended purpose.

Your opinion has been heard. Please do not impose it as the absolute truth! Allow me, as an electronic engineer by education, to at least have the right to state a theory. Are you an electronic engineer by education?

KokoFresha Posted at 2-17 03:33
Your opinion has been heard. Please do not impose it as the absolute truth! Allow me, as an electronic engineer by education, to at least have the right to state a theory. Are you an electronic engineer by education?

It's not an opinion, (but what you stated is).
Do you think that electronic engineers are the only people that understand GPS?
Do you really think that planes and ships can't have a fully functioning navigation system when it rains or is overcast?
Get out of your theoretical engineer mindset and get real.

Labroides Posted at 2-17 03:37
It's not an opinion, (but what you stated is).
Do you think that electronic engineers are the only people that understand GPS?
Do you really think that planes and ships can't have a fully functioning navigation system when it rains or is overcast?

In my first post I tried to explain the principle of reservе. I assure you that every system that is constructed has such a reserve. The more responsible she is, the greater the reserve.
Let me give you an example with your computer: When a heavy program is not running, it most likely consumes less than 100 watts of power. When you load it to the limit, it probably consumes over 300 watts. But your power supply is  500 watts. The difference of 300 to 500 watts is your reserve. It guarantees that in the worst case, your computer will remain operational.
Let us now apply this logic to any radio signal (GPS signals are essentially radio signals). GPS satellites emit radio signals of a certain power. The strength of these signals decreases with distance from the satellite and depends to some extent on the environment through which they pass. When this signal reaches our drones, it is very weak. This is where the antennas come in, which must provide a strong enough signal according to the specifications of the GPS module. Assume that the GPS module needs a signal of at least 0.1 mV. For proper operation in all conditions, you design an antenna that will provide this signal in the worst possible conditions (perfect storm). However, in order to have a reserve, you will construct an antenna with higher sensitivity, or a GPS module that needs a lower minimum signal.

The GPS of ships and planes has a large reserve. They will have stable location data even in the worst conditions, because they are designed for conditions worse than the worst.

KokoFresha Posted at 2-17 05:07
In my first post I tried to explain the principle of reservе. I assure you that every system that is constructed has such a reserve. The more responsible she is, the greater the reserve.
Let me give you an example with your computer: When a heavy program is not running, it most likely consumes less than 100 watts of power. When you load it to the limit, it probably consumes over 300 watts. But your power supply is  500 watts. The difference of 300 to 500 watts is your reserve. It guarantees that in the worst case, your computer will remain operational.
Let us now apply this logic to any radio signal (GPS signals are essentially radio signals). GPS satellites emit radio signals of a certain power. The strength of these signals decreases with distance from the satellite and depends to some extent on the environment through which they pass. When this signal reaches our drones, it is very weak. This is where the antennas come in, which must provide a strong enough signal according to the specifications of the GPS module. Assume that the GPS module needs a signal of at least 0.1 mV. For proper operation in all conditions, you design an antenna that will provide this signal in the worst possible conditions (perfect storm). However, in order to have a reserve, you will construct an antenna with higher sensitivity, or a GPS module that needs a lower minimum signal.

That is exactly my understanding on this matter!

So, now there are two of us...

I also studied physics, among other things, and I understand something about the atmospheric propagation conditions of electrical signals.

But, I also understand Labroides very well, who takes from the publications on this that GPS can (!) also work well under the most diverse weather conditions on our earth.

Clouds always lead to an attenuation of electromagnetic radiation. Light rays - as particularly short-wave electromagnetic waves - are dampened for everyone to see.

Labroides Posted at 2-17 03:37
It's not an opinion, (but what you stated is).
Do you think that electronic engineers are the only people that understand GPS?
Do you really think that planes and ships can't have a fully functioning navigation system when it rains or is overcast?

... it doesn't necessarily have anything to do with understanding GPS (determining one's own coordinates from the signals from satellites), but here in particular with the behavior (the propagation conditions) of electromagnetic waves.

Please don't get confused here...

Many year ago I was selling electronic measuring instruments to Channel 10 or Ch 9 ( can not remember any more) in Sydney. One was to send a pulse up to their satellite and back to check that satellite was in the right position. At that time I looked at a screen in their satellite receiving room and asked what it displays and they said it was the signal strength from the satellite down to their receiver. At the same time a thunder storm with black clouds rolled in and the signal strength dropped significally and the automatic system sent up a pulse to the satellite to put more gain on in order to keep the right strength at earth. So to me, thick clouds can certainly attenuate that type of signals. How many db it was I just can not remember, but enough to up the gain.

frankymusik Posted at 2-15 06:23

Still cutting into important battery time by waiting for satellites,unless I am looking at it wrong.

djiuser_MmmtHkFaa90r Posted at 2-17 11:16
Still cutting into important battery time by waiting for satellites,unless I am looking at it wrong.

If you leave your drone in idle the battery will last 3 hours or more. So 5 minutes will take almost nothing from your battery.

hallmark007 Posted at 2-17 11:21
If you leave your drone in idle the battery will last 3 hours or more. So 5 minutes will take almost nothing from your battery.

hope that is the case,then it would help a little by not having to use much battery power.
I am sure they will still get the issue solved before long.

frankymusik Posted at 2-17 10:43
... it doesn't necessarily have anything to do with understanding GPS (determining one's own coordinates from the signals from satellites), but here in particular with the behavior (the propagation conditions) of electromagnetic waves.

Please don't get confused here...

I have >20 years experience using GPS recreationally and professionally.
I'm not the one that's confused here.
Your theoretical stuff is fine, but in practice, the attenuation is not enough that you would ever notice.
I posted a link that explains it and it's easy to find plenty more.

If you think that GPS reception could be problematic because of clouds, you are fooling yourself.

Labroides Posted at 2-17 11:53
I have >20 years experience using GPS recreationally and professionally.
I'm not the one that's confused here.
Your theoretical stuff is fine, but in practice, the attenuation is not enough that you would ever notice.

If some users here observe that the M3 needs even longer for a GPS lock in heavy cloud cover, then you shouldn't just "wipe that aside"...
Otherwise you could also argue that the M3 has no GPS problems at all, because after all, every smartphone connects to the GPS very quickly after switching it on, right?  
Clouds dampen electromagnetic waves, and this has no effect on the vast majority of GPS receivers.  That is (rightly) also your experience.  
However, you must not conclude from this that this physical influence does not exist at all.  

So let's leave this discussion please as our approach comes from very different experiences/knowledge.

frankymusik Posted at 2-17 12:24
If some users here observe that the M3 needs even longer for a GPS lock in heavy cloud cover, then you shouldn't just "wipe that aside"...
Otherwise you could also argue that the M3 has no GPS problems at all, because after all, every smartphone connects to the GPS very quickly after switching it on, right?  
Clouds dampen electromagnetic waves, and this has no effect on the vast majority of GPS receivers.  That is (rightly) also your experience.  

If some users here observe that the M3 needs even longer for a GPS lock in heavy cloud cover, then you shouldn't just "wipe that aside"...
On the contrary, some users might think that cloud cover is responsible for variations in GPS acquisition time, but they don't understand that GPS acquisition time is not constant and varies anyway, regardless of cloud cover.

Otherwise you could also argue that the M3 has no GPS problems at all, because after all, every smartphone connects to the GPS very quickly after switching it on, right?
You've lost me there .. I can't see the logic in what you are saying.

Clouds dampen electromagnetic waves, and this has no effect on the vast majority of GPS receivers.  That is (rightly) also your experience.  
That's exactly what I've said all along.
Sounds like you are agreeing ?

Sorry, Labs, but cloud cover DOES affect gps reception. The same way it affects satellite tv reception. It is a radio wave. Nothing more, nothing less. The difference is the sensitivity of the receiver and the internal processing. Somehow DJI has screwed up the processing.

Mobilehomer Posted at 2-17 13:52
Sorry, Labs, but cloud cover DOES affect gps reception. The same way it affects satellite tv reception. It is a radio wave. Nothing more, nothing less. The difference is the sensitivity of the receiver and the internal processing. Somehow DJI has screwed up the processing.

Sorry, Labs, but cloud cover DOES affect gps reception.
It doesn't affect it to a degree that you would notice.
Read this link: http://gpsinformation.net/gpsclouds.htm

GPS uses frequencies particularly chosen for their ability to penetrate weather.
Satellite TV is not using the same frequencies.

Labroides Posted at 2-17 14:07
Sorry, Labs, but cloud cover DOES affect gps reception.
It doesn't affect it to a degree that you would notice.
Read this link: http://gpsinformation.net/gpsclouds.htm

Just how good is the dji receiver/antenna and processing arrangement? None of us know. We do know what chipset is being used, but not how.

Labroides Posted at 2-17 13:35
If some users here observe that the M3 needs even longer for a GPS lock in heavy cloud cover, then you shouldn't just "wipe that aside"...
On the contrary, some users might think that cloud cover is responsible for variations in GPS acquisition time, but they don't understand that GPS acquisition time is not constant and varies anyway, regardless of cloud cover.

On the contrary, some users might think that cloud cover is responsible for variations in GPS acquisition time, but they don't understand...
... these are user observations here, not scientific studies, and you can't simply "wipe away" them using experiences you've gained with other GPS receivers...
And therefore once again: Based on the experience gained so far (with partly completely different hardware and software) one cannot solve a "completely new" problem...
You would never get any further with your knowledge that way!

You've lost me there .. I can't see the logic in what you are saying.
That was meant somewhat ironically, perhaps too abbreviated.
Your argument often runs along the lines of "I have 20 years of experience, so I'll say what's right here...".
So you could also claim that the M3 has no GPS problems at all, because (in your experience) every smartphone recognizes its location immediately after switching it on.
Yes, I made it a little easier for myself with this sentence...

That's exactly what I've said all along.
Sounds like you are agreeing ?
No, that's wrong!
The following sentence (in my post 24#) is part of my statement! This read:
"However, you must not conclude from this that this physical influence does not exist at all."

For your information:
In 2017 I developed a process (software) for a large German automotive supplier that deals with the topic of "dead reckoning" in moving automobiles.
It's about being able to provide the (as exact as possible) GPS coordinates despite disturbed GPS reception...
This is about having the GPS coordinates available at all times when driving through "deep urban canyons" or when driving through underground areas and so on. If an accident happens, such vehicles automatically (via mobile phone network) make an emergency call to get help. If the GPS signal cannot currently be received (or only poorly), this emergency call system would not be available. In large cities, however, it is also very important to lead the emergency services to the scene of the accident...
In the automobile, this (alternative) GPS coordinate determination can be calculated fairly accurately from the "old" (correct) GPS signals and the current vehicle data (vehicle speed, steering angle, yaw rate, ...). That was the solution to that problem...
During this time I had a lot to do with the possible interference with the GPS reception. That's why I have the courage to share my opinion on such topics here...

If you would like more information on this, please PM me. I would then send you excerpts of the documentation from 2017 if you are also interested in this topic...

frankymusik Posted at 2-18 00:04
On the contrary, some users might think that cloud cover is responsible for variations in GPS acquisition time, but they don't understand...
... these are user observations here, not scientific studies, and you can't simply "wipe away" them using experiences you've gained with other GPS receivers...
And therefore once again: Based on the experience gained so far (with partly completely different hardware and software) one cannot solve a "completely new" problem...

Sorry ... I can't follow what you are saying.
It's just confusing.
Maybe it's a language issue ?


And nothing you've said indicates that GPS reception is attenuated by rain or clouds enough that you would ever notice.
Just that theoretically there would be some attenuation.

GPS was designed as an all-weather navigation system and it works very well at that using appropriate radio frequencies that can penetrate even heavy rain.
Clouds don't ever cause problems for GPS users.

Labroides Posted at 2-18 03:25
Sorry ... I can't follow what you are saying.
It's just confusing.
Maybe it's a language issue ?

Maybe it's a language issue ?
Yes of course, language can also be a "problem", I'm not a native English speaker...

But, some users in this forum have already tried to bring you closer to "the somewhat different way of thinking"...
I try one last time...:

... with a well-designed GPS system (both the hardware is robust and the software has been well adapted) you will have no GPS reception problems (under the open sky!), of course not even if the sky is very cloudy.
But, in the border area of ​​undisturbed reception, as already mentioned, in narrow street canyons, in the forest,...
... there is definitely a measurable difference in the signal strength if you have a cloudless sky or heavy cloud cover!

You can also test this at home (i.e. inside the house)!
Put your GPS receiver in a well-defined place where you can just pick up a few (that is, a few) satellites when the sky is clear. Mark this position very precisely, also the angle in a defined direction that you used.
Then repeat the experiment in heavily overcast, rainy weather. Note the number of satellites then received.
Repeat the experiment many times to gain some statistical confidence.
Then evaluate your observations and please report back here with your results.

Of course, you only have to do this in this way if you do not have a GPS measuring device to record the signal strength of the satellites. Of course, the direct measurement brings the knowledge much faster, less expensive!

And as I said, this has no noticeable influence on a well-designed GPS device (except in the cases described).
But that's exactly what these forum posts aren't about (a "well-designed GPS receiver").
The M3 users have problems with the GPS reception (already with a clear sky), and therefore they "investigate" the influence of disturbing factors, such as nearby trees, buildings, ..., heavily overcast sky, "bad" weather as well...

That should have been understandable now, right...???

Labs, maybe this will help - IT'S NOT THE SIGNAL!!!! IT'S THE RECEIVER!!!

frankymusik Posted at 2-18 05:02
Maybe it's a language issue ?
Yes of course, language can also be a "problem", I'm not a native English speaker...

The M3 users have problems with the GPS reception (already with a clear sky), and therefore they "investigate" the influence of disturbing factors, such as nearby trees, buildings, ..., heavily overcast sky, "bad" weather as well...

The M3 GPS is very bad no matter what the flying conditions are.
It's not a result of poor weather.
It just doesn't acquire a suitable number of sats for a receiver that should be picking up sats from 3 constellations.

Labroides Posted at 2-18 05:30
The M3 GPS is very bad no matter what the flying conditions are.

... earlier you said that the influence of the weather (clouds, etc.) is not noticeable.
I've shown you how you can see that influence - even in your own home...

Now dodge again with other arguments.
I don't feel like having such "discussions" anymore, which can never soften the point of view....

Mobilehomer Posted at 2-18 05:29
Labs, maybe this will help - IT'S NOT THE SIGNAL!!!! IT'S THE RECEIVER!!!

That's irrelevant to what's being discussed.

frankymusik Posted at 2-18 05:02
Maybe it's a language issue ?
Yes of course, language can also be a "problem", I'm not a native English speaker...

That should have been understandable now, right...???
Not even a little.

You talk down to me like I don't understand GPS.
I have a science degree and am a working scientist with a lot of experience using GPS for >20 years.
I'm not a dummy.
How is it that so many others all over the world commonly advise that GPS is not affected by clouds or weather to a degree that you could notice?Here are a few examples that are quickly found.Tell me why they are all wrong.


Does RAIN or SNOW or CLOUDS affect the reception of my GPS receiver?
No.  Not so as the user can tell without instrumentation.
http://gpsinformation.net/gpsclouds.htm

The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the earth where there is an unobstructed line of sight to four or more GPS satellites.
https://www.land-surveyors-perth.com.au/faq/what-gps

Originally developed for military use, GPS is extremely accurate and is able to be used in any weather conditions and all destinations across the globe.
https://fleetlog.com.au/info/what-is-gps-tracking.html

the system is independent of weather conditions
https://www.sage.unsw.edu.au/sit ... phSeries/mono17.pdf
Page 89

GPS works in any weather condition, anywhere in the world, 24 hours a day
https://www.imua.org/Files/reports/999110.html#adv

Although some atmospheric conditions like rain or snow can weaken the GPS signal, they generally do not affect GPS reception
https://www.frotcom.com/blog/201 ... affect-gps-accuracy

frankymusik Posted at 2-18 05:39
... earlier you said that the influence of the weather (clouds, etc.) is not noticeable.
I've shown you how you can see that influence - even in your own home...

... earlier you said that the influence of the weather (clouds, etc.) is not noticeable.
I've shown you how you can see that influence - even in your own home...

I'm not going to continue a discussion with someone that suggests that flying inside a home somehow proves that clouds affect GPS reception.
That's just ridiculous.
And you talk like I have no idea !!!!

Labroides Posted at 2-18 05:52
... earlier you said that the influence of the weather (clouds, etc.) is not noticeable.
I've shown you how you can see that influence - even in your own home...

Oh, but you have thoroughly misunderstood.
It can't be a language problem!
You just want to provoke, right?

I suggested that you use any kind of GPS receiver (never with your Mavic 3!) to take measurements in your house by placing this receiver in the same place (inside the house) over and over again (in different weather conditions) and making a note of it , how many satellites this receiver "sees"...
To do this, you have to "place" this receiver a little further away from the window so that you can only receive a few satellites when the sky is clear.
If you then repeat these measurements in rainy weather, please register the difference, i.e. how many satellites does your GPS receiver receive under these conditions....

Labroides Posted at 2-18 05:45
That's irrelevant to what's being discussed.

It is the MOST relevant thing in the discussion!!! We are discussing the M3 TTFF. If DJI has hobbled the receiver, it IS the receiver NOT the signal!!

Labroides Posted at 2-18 05:52
... earlier you said that the influence of the weather (clouds, etc.) is not noticeable.
I've shown you how you can see that influence - even in your own home...

Being perfect,it must be nice.