How does the Wifi work on a P3S?

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In regards to my P3 Standard with poor range. I've been flying both the Standard and my Pro for a long time now. But I'm not sure I really understand how the Standard Wifi system works. This is how I think it works, correct me is I'm wrong.

The RC unit broadcasts the Wifi signal to the Phantom. It is a one way signal. I believe it sends commands to the drone for maneuvering, but receives nothing in return. It uses the RC center pole antenna to do this. The P3S sends out a constant stream of data to the RC unit, which in turn is displayed for the pilot. That telemetry consists of video display and all of the instrument readings such as speed, distance, altitude, etc,etc. That features uses the two paddle antennas in the RC unit to receive the signal. But how is the signal generated in the drone? Does it also have a Wifi transmitter?

In my case, the video feed never falters. It's the maneuvering signal that is lost. If I can get a better understanding of how these two signals work, I think I can narrow down the reason why I lose signal at such short range. The above is just my understanding, it may not be fact. If someone can explain the "Maneuvering" signal to me in greater detail, I would certainly appreciate it.
 
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With the Phantom 3 Standard, the communication between the AC, the RC, and the DJI Go app is all over Wi-Fi. It's bi-directional and uses both the 2.4 and 5.8 Ghz bands. The RC talks to the AC over 5.8 Ghz for the controls. The telemetry data and video are sent over the 2.4 Ghz band.

The 5.8 Ghz antenna is the external one. You can cheaply increase the range with one of the parabolic signal boosters that slide over the antenna. I have this one, but there are others out these. In terms on orienting the antenna to the AC to get the best signal, you want the center antenna to be perpendicular to the AC. So if the AC is away from you, the antenna should be vertical. If the AC is directly above, you would fold down the antenna.
 
Yes, the 5.8g is the drone control uplink, and 2.4g is the video and telemetry downlink. They are independent of each other.
My understanding is:
If the drone lost the 5.8g signal, you will get a "RC Signal Lost" in your notification, you won't get a "RTH - OK or Cancel" prompt on the display to cancel RTH . However, if the RC lost the 2.4g signal, you'll get a "RTH - OK or Cancel" window and you can cancel RTH and continue to fly without video for a while.
 
OK .... let's correct this ...

1. The centre antenna is 5.8ghz and is a one way control signal to the model from the controller. It provides the flight command signals based on your input to controller on the ground.
2. The internal antenna in the controller are the 2.4ghz WiFi and are two way communication to the model. They also communicate with the tablet / phone you use. The WiFi provides the communication that relays all video and telemetry data to / from model.

Let's take you flying. You power all up and display unit locks onto the controller WiFi. Controller has locked onto model with both 5.8 and WiFi.
You tap the auto-takeoff icon. The display sends a command to the controller via the WiFi. The controller then sends this to model flight controller via 5.8. Model takes off.
You alter camera / tilt - this is again display to controller but camera command goes to model by WiFi. This is why when updates fail etc. - you can still alter camera ...

All flight commands are 5.8ghz .... all video and telemetry are 2.4ghz.

Now onto RTH.

If you lose 5.8ghz link to model - it will automatically after a few seconds initiate RTH if that is set in app. RC signal lost usually displayed and then Going Home. The controller starts beeping indicating going home. Depending on app used - you do not always get RC signal lost warning.

If you lose wifi connection to model - RTH does not initiate, as you still have control 5.8. This is where panic hits the inexperienced ! Its also where the advice to restart app is not such a good idea ! best is to hit S2 switch and manually initiate RTH.
When WiFi is lost to the model - usual result is model hovers where it is waiting for you to decide what to do. You get a warning Video signal lost --- IF the app is still working ! When its happened to me - usually the last video frame is shown or the app / tablet has shut down.

To summarise :

5.8ghz provides one way command control for flight.

2.4ghz provides two-way video and telemetry data link to /from model / controller.

RTH is auto initiated when 5.8ghz link fails.... unless owner sets different failsafe action.

Model remains in control when 2.4ghz link fails, it does not RTH.

Nigel
 
Model remains in control when 2.4ghz link fails, it does not RTH.
IMO, that's incorrect.
If you look through your flight logs, you can see these two different types of RTH:
2.4g signal lost RTH:
07:18 (Data Loss) Downlink data connection lost for 32.1 seconds
07:18 (Mode) Mode changed to Go_Home
(Notes: I did not initiate the RTH here)
5.8g signal lost RTH
06:31 (Tip) Tips_Signal Lost. Aircraft returning to Home Point
06:32 (Mode) Mode changed to Go_Home

If the downlink signal gets lost for a significant amount of time, the App *will* remind you to RTH, and if you ignore the warning and not hit the "Cancel" button, the RTH is triggered by default.
 
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I have had two occasions where 2.4 has failed and model sat hovering ......... I flicked S2 and she came home. She never initiated RTH herself ....

It may be that a full failure of CONTROLLER signal of 2.4 or 5.8 initiates RTH but that is unusual to have the 2.4 signal of the controller fail. Usually it is the AC signal back that goes weak or fails - then you get the WEAK or VIDEO signal lost warning. I have had AC 2.4 signal lost on numerous occasions and never had RTH yet. But as far as I know not a full Controller failure. But I have had a tablet shut down ... WiFi stop etc. - and again because I didn't know status of AC ... let go sticks and she hovered.

Nigel
 

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