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GPS satelite data transmission signals - what kind are they?

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Trying to get a handle on some odd issues with GPS signals. I think that most of us know that are drone systems use both 2.4Ghz and 5.8Ghz signals. If I understand it correctly(in the most basic sense) the 2.4 signal is for movement communication of the drone and the 5.8 is for the video transmission. And, our RC systems also have 2 antennas for this. But, what are the GPS signals that come from the sats and do we have other antennas in each the controller and the A/C for them?
 

h-elsner

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GPS L1 Band: 1575.42 MHz with a bandwidth of 15.345 MHz
GPS L2 Band: 1227.6 MHz with a bandwidth of 11 MHz
GPS L5 Band: 1176.45 MHz with a bandwidth of 12.5 MHz

GPS receiver has its own antenna. It looks like this:
gps_antenna.jpg

ST16 has 5 antennas:
two for 2.4GHz ZigBee RC connection (antenna diversity). Some has both outside, older ones have one outside, on inside
one 5Ghz Wifi outside (mushroom or patch antenna)
one 2.4GHz Wifi inside
one GPS antenna

The drone has 3 antennas:
two for 2.4GHz ZigBee RC connection (antenna diversity)
one GPS antenna

The camera has one antenna for 5GHz WiFi band.

br HE
 
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GPS L1 Band: 1575.42 MHz with a bandwidth of 15.345 MHz
GPS L2 Band: 1227.6 MHz with a bandwidth of 11 MHz
GPS L5 Band: 1176.45 MHz with a bandwidth of 12.5 MHz

GPS receiver has its own antenna. It looks like this:
View attachment 28745

ST16 has 5 antennas:
two for 2.4GHz ZigBee RC connection (antenna diversity). Some has both outside, older ones have one outside, on inside
one 5Ghz Wifi outside (mushroom or patch antenna)
one 2.4GHz Wifi inside
one GPS antenna

The drone has 3 antennas:
two for 2.4GHz ZigBee RC connection (antenna diversity)
one GPS antenna

The camera has one antenna for 5GHz WiFi band.

br HE
Thanks so much HE. I'm going somewhere with this info for a future post. I will also link this info to the new post when created.

I also take it that the above bands and freqs are for the USA GPS system. Does the EU and Russian systems use their own receivers? The bands and freqs are not needed for my interests. But, if so, would a flyer using a drone for the EU or Russian market need to replace the receiver if it was to be flown in the US? And, are these user replaceable? Or, because the sats orbit the earth it is not needed to replace a receiver? I also take it that our drones only have GPS receivers which they relay back and forth with the controller for location/flight accuracy and have no GPS transmitters.
Are the GPS receivers a government made device and then sold to tech companies, or is it licensed out?
 

h-elsner

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The frequencies are nearly the same from antenna point of view. I mean, you do not need another antenna. All other things like kind of modulation (i.e. FDMA vs. CDMA), channel settings, noise, calculation methods and so on are realized in a so called system-on-chip (SOC). There are some vendors like Broadcom, u-blox and other.

Yuneec uses U-Blox M8Q chip that supports GPS, GLONASS, Galieo, and can use 3 of them concurrent. As far as I know the Yuneec FW has selected GPS and GLONASS out of this set of systems. However, all GNSS systems (it's better to say GNSS when one mean all 'GPS' systems) are made to work worldwide, maybe with different precision depending on preferred areas. There is no need to have special GPS receiver for the dedicated area or system. The GNSS system in our vehicles are only receiver, nothing will be transmitted back to the sats.
You can download the datasheet from the u-blox M8 chip and read a lot of features and how it works.

br HE
 
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If you want to analyze what is in these spectrums I use Hack RF with an app call RF Analyzer 1.13 which runs up 6Ghz. WIth this tool you can really see what is going on in your band. I am 60 miles northwest of Chicago at a high point and there is a 300ft mast about 500 ft from my take off area. I like seeing what I am connected to.
 
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I and many users of this forum know that the Yuneec manuals leave a lot of info out. Since it is very unlikely that we will ever see an indepth user manual of our drones come from Yuneec, this user site/forum is of great value to all of us.

I do appreciate all the technical info that the above users have supplied. I wasn't expecting this, but, it's worth noting that there are many users of this forum who have awesome knowledge concerning many aspects that keep our drones in the air. This forum has increased my understanding of drone use and safe flight. Many thanks to those who help the rest of us.
 

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