Question about Radio, uplink, downlink, frequency, & telemetry

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I have a Phantom 3 Standard, and have not been able to fully understand the communications loops on my device. My guess is this:

Controller transmits signals (uplink?) to aircraft via single external antenna..... on 5.8 Gig frequency
Aircraft sends signals (downlink?) to controller's internal dual flat antennas .... on 2.4 Gig frequency
Aircraft sends signals to my android tablet via wifi ....on 2.4 Gig frequency
Tablet sends signals to aircraft via wifi ... on 2.4 gig frequency (does tablet transmit directly to drone?)

Does it work like this? ........ Am I close?

Additionally, which of the above communications links benefits from a parabolic (wind surfer) antenna add-on?

(just wondering)
 
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I have a Phantom 3 Standard, and have not been able to fully understand the communications loops on my device. My guess is this:

Controller transmits signals (uplink?) to aircraft via single external antenna..... on 5.8 Gig frequency
Aircraft sends signals (downlink?) to controller's internal dual flat antennas .... on 2.4 Gig frequency
Aircraft sends signals to my android tablet via wifi ....on 2.4 Gig frequency
Tablet sends signals to aircraft via wifi ... on 2.4 gig frequency (does tablet transmit directly to drone?)

Does it work like this? ........ Am I close?

Additionally, which of the above communications links benefits from a parabolic (wind surfer) antenna add-on?

(just wondering)
First part was correct, but after that you kinda messed up.
Control: Controller➡Aircraft (5.8ghz)
Video Downlink: Aircraft
➡Controller (2.4ghz)
Device Video Downlink: Controller
➡Device (2.4ghz)
Device Control: Device➡Controller (2.4ghz)
The Controller makes it's own WiFi Network, the device doesn't communicate directly with the aircraft.
 
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Thanks. I presume that "device" = the smartphone/tablet.

Now, which antennas are associated with which functions? ( stick antenna, plus the internal 2 paddle antennas onside the controller)
 
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Stick is 5.8ghz and the 2 internal one are 2.4ghz. P3S aircraft uses 2.4ghz downlink video to the controller using WiFi. For P3P/A, the aircraft also uses 2.4ghz but using Lightbridge. Lightbridge is a one way broadcast communication which doesn't require packet resend if a byte is lost. Wifi requires two way handshake so if a byte is dropped, the whole 512 byte in the packet has to be resent. That's why P3P/A has much better live video feed.


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External white antenna is 5.8ghz 1 way uplink transmitter only. This is all the analogue movements on your controller. Eg flip switches and control sticks.

Internal 2.4 antenna is a patch 2.4ghz 2 way communications via traditional wifi. When you press buttons on your screen like taking a photo, it uses the 2.4 ghz wifi to send instructions UP to the P3Std. When you are looking at the sat/bat telemetry it is using the DOWN link to receive data. And obviously, FPV is also using the DOWN link.
 
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Very interesting. Most of us know how to use this technology , but don't know how the technology works ! I'm still not sure of the linkage for GPS signals ? ? Is it OK to stand under a tree ( for shade ) for GPS reception - with quad in front of tree in los.


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Mark The Droner

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Yes you can stand under tree provided aircraft is out in the open at least somewhat. But you might find your own fix for your device is bouncing around a bit.
 
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Thanks I thought so. Still not sure how GPS works ! Does quad pickup GPS direct relay back to tablet/phone or per controller ?
 

Mark The Droner

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The one thing I am not sure about is how, like exactly, does the data move from the controller to the mobile device. My understanding is, the data is relayed on a different wifi freq. That's fine, but what transmitter is used? There are two transmitters. What about switching? Does it use either transmitter and is completely random depending on what's going on?
 

RodPad

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External white antenna is 5.8ghz 1 way uplink transmitter only. This is all the analogue movements on your controller. Eg flip switches and control sticks.

Internal 2.4 antenna is a patch 2.4ghz 2 way communications via traditional wifi. When you press buttons on your screen like taking a photo, it uses the 2.4 ghz wifi to send instructions UP to the P3Std. When you are looking at the sat/bat telemetry it is using the DOWN link to receive data. And obviously, FPV is also using the DOWN link.
When you press buttons on your screen? Your sending instructions UP to controller, then controller sends it to the bird, Correct?
This is why I don't rely on the RTH button on the device to actually activate RTH.
 

RodPad

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The one thing I am not sure about is how, like exactly, does the data move from the controller to the mobile device. My understanding is, the data is relayed on a different wifi freq. That's fine, but what transmitter is used? There are two transmitters. What about switching? Does it use either transmitter and is completely random depending on what's going on?
If read your post correct, that answer is on post#2, it creates its own wifi network.
 
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When you press buttons on your screen? Your sending instructions UP to controller, then controller sends it to the bird, Correct?
This is why I don't rely on the RTH button on the device to actually activate RTH.
If you trigger RTH on the physical controller, it is sent via the 5.8ghz antenna > 5.8ghz receiver board > main board > NAZA.
If you trigger RTH on the screen, it is sent via the 2.4ghz patch antenna > 2.4ghz wifi module > main board > NAZA.
 

RodPad

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So was I correct? That is why the button on the app my not actually work, if the app happen to fail sending the command via Wifi to the remote?

I guess the other confusion is either way if RTH was initiated, but the signal coming back from the bird is lost, the app doesn't display RTH is activated.
 

Mark The Droner

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The nice thing about turning off your controller is you KNOW Rth is activated. You don't have to worry. Just relax and pop a beer
 

RodPad

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The nice thing about turning off your controller is you KNOW Rth is activated. You don't have to worry. Just relax and pop a beer
Yes I have done that, both ;), but then you loose your flight log, so that is the my last choice, but in about 5 second window.:eek:
 
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Hmm... so what is the benefit of a wind surfer parabolic antenna device if it only improves the outgoing signal?
 
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I found a way to remove the internal WiFi Module inside the P3S Controller and house it in an external enclosure with its own battery. No soldering or wire cutting.

Along with the REDbird 5.8ghz RC Repeater Module, that makes a complete repeating solution for the P3S.

Mount both ontop our car and sit comfortably inside wile maximizing your range.
Two man team: car driver and drone operator.

Or mount the repeater pair on a second Repeater-Helper Drone and let it over over head.
 

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