Hello everybody,
although I live in Italy and will probably never see the Mavic 3 working with the dongle for myself, I would love to know more.
I have seen some videos of its operation during the flight.

I ask some questions:

1) it works only for video return or also for commands?
2) is the operation bidirectional? Controller <-> drone?
3) when the radio connection fails, does it completely replace this communication?


Now I go more specifically:
4) In some countries the cellular SIM cards are behind a NAT infrastructure and cannot be reached directly. Does DJI use a proxy or a reverse callback to make the drone and the remote control communicate?
5) how does the drone behave in case of latency? Sometimes the handover between one cell and another can suffer disconnections.
6) Even if it uses a proxy, how does it deal with latency?

Other technical questions come to mind but let's start with these.

I cannot answer those very technical questions but my understanding of how it works in layman terms is : When the RC Pro and M3 have the LTE dongle connected, it uses 4G for transmission of video and RC controls to the drone, this gives the Mavic 3 an unlimited flight distance or as far as you have 4G signal. From what I have read is that there is a monthly cost associated with buying this dongle.

Suren Posted at 2-18 22:50
I cannot answer those very technical questions but my understanding of how it works in layman terms is : When the RC Pro and M3 have the LTE dongle connected, it uses 4G for transmission of video and RC controls to the drone, this gives the Mavic 3 an unlimited flight distance or as far as you have 4G signal. From what I have read is that there is a monthly cost associated with buying this dongle.
https://youtu.be/sxOs4quGgzU

Thank you Suren,
let's start putting some pieces of this puzzle.
So there is a subscription to do, which assumes an acknowledgment server and probably some sort of proxy between the two SIM cards.

Let's see if someone else will help us to understand how it works.

1) it works only for video return or also for commands?

- It works for both, but places higher priority to transfer commands over video data.

2) is the operation bidirectional? Controller <-> drone?

- Yes it is bi-directional. Which is why the RC-N1 controller requires one dongle (installed on the drone), but RC-PRO controller requires two (one on the drone, one inside the controller).

3) when the radio connection fails, does it completely replace this communication?

- Yes.

4) In some countries the cellular SIM cards are behind a NAT infrastructure and cannot be reached directly. Does DJI use a proxy or a reverse callback to make the drone and the remote control communicate?

- DJI does not recommend using SIM cards behind a NAT infrastructure.

5) how does the drone behave in case of latency? Sometimes the handover between one cell and another can suffer disconnections.

- In theory, there is a seamless switch between controller/4G signal, which ever is stronger. In reality, some users have reported video transmission interruption/disconnections between the drone and controller, in areas where both controller and 4G signal are weak or not available.

6) Even if it uses a proxy, how does it deal with latency?

- It cannot. The dongle is not a magic bullet to solve all the connection problem. There is only so much it can do.

Suren Posted at 2-18 22:50
I cannot answer those very technical questions but my understanding of how it works in layman terms is : When the RC Pro and M3 have the LTE dongle connected, it uses 4G for transmission of video and RC controls to the drone, this gives the Mavic 3 an unlimited flight distance or as far as you have 4G signal. From what I have read is that there is a monthly cost associated with buying this dongle.
https://youtu.be/sxOs4quGgzU

Your understanding is not entirely accurate.

The 4G LTE dongle works for both RC-N1 and RC-PRO controller. The dongle only kicks in when the radio signal drops between the controller and the drone. It then uses 4G network to transfer both video and control command between the drone and the controller. User pays an annual subscription fee of 99 RMB to DJI, in order to use their dedicated data relay server for the service.

DJI designed this dongle for one particular scenario - to have a smooth flight in city metro area, where radio signals are easily blocked/interrupted by high-rise buildings. With the dongle, pilots can now fly full circle around tall buildings, without worrying about losing connections.

jerryway Posted at 2-19 11:40
Your understanding is not entirely accurate.

The 4G LTE dongle works for both RC-N1 and RC-PRO controller. The dongle only kicks in when the radio signal drops between the controller and the drone. It then uses 4G network to transfer both video and control command between the drone and the controller. User pays an annual subscription fee of 99 RMB to DJI, in order to use their dedicated data relay server for the service.

Ok now I understand, you answered to many of my questions.
One for all is that you have to pay DJI to use their dedicated data relay server.  So it is possible that is not a proxy server but an apn (access point name) service that you have to configure in your SIM card.

Yes it sounds good.

jerryway Posted at 2-19 11:40
Your understanding is not entirely accurate.

The 4G LTE dongle works for both RC-N1 and RC-PRO controller. The dongle only kicks in when the radio signal drops between the controller and the drone. It then uses 4G network to transfer both video and control command between the drone and the controller. User pays an annual subscription fee of 99 RMB to DJI, in order to use their dedicated data relay server for the service.

Hi Jerryway, Thanks for clearing that up but I highly doubt that the 4G dongle will work with the standard RC. The reason for this is the the RC will need to have an internet connection from hot spotting to the cellular network or wifi to be able to connect via 4G to the Drone, the standard controller does not have the ability to connect to the internet nor does it have the ability to hotspot wifi, it is just what its advertised as, a standard controller. See the specifications for it, it is only listed for RC Pro.

Suren Posted at 2-19 13:06
Hi Jerryway, Thanks for clearing that up but I highly doubt that the 4G dongle will work with the standard RC. The reason for this is the the RC will need to have an internet connection from hot spotting to the cellular network or wifi to be able to connect via 4G to the Drone, the standard controller does not have the ability to connect to the internet nor does it have the ability to hotspot wifi, it is just what its advertised as, a standard controller. See the specifications for it, it is only listed for RC Pro.

[view_image]

No need to doubt that 4G dongle works with the standard controller. It is a simple fact, which unfortunately has been obscured by the poor English description of the 4G dongle on DJI's website.

The standard controller is paired with your phone. Your phone has the ability to connect to the internet, or a hotspot wifi. It then talks to the dongle mounted on the drone, via DJI's data relay server. This is why RC-N1 needs only one dongle, while RC-PRO needs two.

jerryway Posted at 2-19 13:53
No need to doubt that 4G dongle works with the standard controller. It is a simple fact, which unfortunately has been obscured by the poor English description of the 4G dongle on DJI's website.

The standard controller is paired with your phone. Your phone has the ability to connect to the internet, or a hotspot wifi. It then talks to the dongle mounted on the drone, via DJI's data relay server. This is why RC-N1 needs only one dongle, while RC-PRO needs two.

I did not know that, thanks.

But the main question is, does the dongle when exchanging information via the Chinese servers block any non Chinese LTE 4g signals ?

Any update on this topic?
Has anyone successfully tried the 4G-Dongle in the US?

https://bbs.dji.com/forum.php?mod=viewthread&tid=294747

Raf_IZ0QWM Posted at 2-23 21:32
https://bbs.dji.com/forum.php?mod=viewthread&tid=294747

Thank you, it's the most detailed information we've seen so far

Just watched a video of a guy in Moscow with a working Mavic 3 using the 4g dongle, so does work outside China at least.

This is a TD-LTE device, so the network has to be TD-LTE as well (and not FD-LTE). TD-LTE networks are found mostly in China. They do exist in other countries in Asia, but not in EU and probably not in the US.
Latency will definitely be an issue, this is difficult if not impossible to be avoided, it's a cellular network after all.
Regarding connectivity, CGNAT is usually deployed in cellular networks, so direct communication via configurations that open ports etc. is not possible. Doubt that DJI has chosen this path though.

mcde Posted at 2-27 23:58
This is a TD-LTE device, so the network has to be TD-LTE as well (and not FD-LTE). TD-LTE networks are found mostly in China. They do exist in other countries in Asia, but not in EU and probably not in the US.
Latency will definitely be an issue, this is difficult if not impossible to be avoided, it's a cellular network after all.
Regarding connectivity, CGNAT is usually deployed in cellular networks, so direct communication via configurations that open ports etc. is not possible. Doubt that DJI has chosen this path though.

In Italy we use the LTE duplex time division on one frequency and one operator only.
For sure DJI uses a private APN.

Suren Posted at 2-19 13:06
Hi Jerryway, Thanks for clearing that up but I highly doubt that the 4G dongle will work with the standard RC. The reason for this is the the RC will need to have an internet connection from hot spotting to the cellular network or wifi to be able to connect via 4G to the Drone, the standard controller does not have the ability to connect to the internet nor does it have the ability to hotspot wifi, it is just what its advertised as, a standard controller. See the specifications for it, it is only listed for RC Pro.

[view_image]

FDD-LTE  or TD-LTE?   

mavic3tw Posted at 3-17 05:47
FDD-LTE  or TD-LTE?

So I was wrong with that comment, it does work on the standard RC-N1

DroneBuffer Posted at 3-17 09:55
So I was wrong with that comment, it does work on the standard RC-N1

It seems to work with both FDD and TDD.
How does it work with the standard controller? When is the enanced function activated? When does the drone tell the controller that it has the dongle plugged in?

Raf_IZ0QWM Posted at 3-21 13:12
It seems to work with both FDD and TDD.
How does it work with the standard controller? When is the enanced function activated? When does the drone tell the controller that it has the dongle plugged in?

jenzeee0 Posted at 2-23 15:51
Any update on this topic?
Has anyone successfully tried the 4G-Dongle in the US?

Sadly someone has tried it in the U.S. and it doesn't work...tried it in the RC-Pro and standard controller that comes with the Mavic 3.  Even went so far as to buy two new data SIM cards, one for each device.

The lights on both modems flash green which means they're connected to the mobile network but they don't have a strong signal.  I can confirm the RC-Pro connects successfully with the mobile network because it downloads data and even shows the mobile carrier name on the Android page, but the icon with the "4G" does not appear in the DJI Fly app as it does in the videos from Australia and China. Also, if you go to the DJI Fly app "Transmission" page there is no option other than 2.4 and 5.8Ghz.

I'm curious to know if the limitation is due to

• The location (geofence written into the code for restricted countries)
• The user's origin country (where the account was set up because each device is tied to a user's account)
• The country of the mobile network (e.g., restricting when the SIM card has a country code of +1 which is for the U.S.)
• The location where the device was purchased (unlikely but DJI could flag this on orders it fills)
• Or something else like I'm not paying for the service others have mentioned
  

I travel internationally and would like to bring the Mavic 3 to a country where I could try this out but I'm not going to go to all that trouble to discover I have a restriction based on the origin of my login or the origin of the SIM card.

Shafted by DJI again, the list is never ending, confirmed non working in the UK I love this drone, but feel like its full potential will never be fully released.

Tony64 Posted at 3-26 15:11
Shafted by DJI again, the list is never ending, confirmed non working in the UK I love this drone, but feel like its full potential will never be fully released.

You could buy them from Aliexpress before but now when I checked there, they don't ship to outside of China, looks like Dji put a block to that very quickly.

Still allowing me to place an order, but I don't want two non working sets, what a let down this has turned out to be, such a wasted opportunity that DJI let go down the pan again.

Just tried this in Australia,  It worked okay but as been regional the signal just said weak alot and kinda defeated the purpose

Hi All,

    I just ordered 2 DJI Mavic 3 Cellular Dongles + drone holder and I am in US. Wanted to ask if anyone had any luck getting it to work in US with RC-N1 controller and cell phone + Dongle on the drone itself or with RC Pro and Dongle + Dongle on the drone (2 dongles). I have Verizon cellular provided, which is CMDA + LTE 4G.  Wonder if anyone got it to work and also with Verizon or maybe a different cellular carrier, am open to getting an extra line with another carrier if needed.

Thanks in advance, Mike.

Has anyone else in Australia had any luck in getting these 4g dongles to work, still yet to see a video of anyone here actually flying with this working. Have noticed the Aliexpress sellers now state the dongle they are selling as a “TDD-LTE Version” which seems we have only 2300MHz (B40) TDD (0000008000000000) – Optus (Vivid wireless spectrum, metropolitan area), NBN (regional area including Gold Coast) and 3500MHz (B42) TDD (0000020000000000) – Optus, NBN (NBN trials at this stage).

Suren Posted at 2-18 22:50
I cannot answer those very technical questions but my understanding of how it works in layman terms is : When the RC Pro and M3 have the LTE dongle connected, it uses 4G for transmission of video and RC controls to the drone, this gives the Mavic 3 an unlimited flight distance or as far as you have 4G signal. From what I have read is that there is a monthly cost associated with buying this dongle.
https://youtu.be/sxOs4quGgzU

This video said that the mavic 3 is waterproof.
It is definitely not waterproof.

(EDITED) I mailed the operators here in Thailand to see for the setting with APN. Hope I can use it here.

Mzp Posted at 7-14 07:29
Hi All,

    I just ordered 2 DJI Mavic 3 Cellular Dongles + drone holder and I am in US. Wanted to ask if anyone had any luck getting it to work in US with RC-N1 controller and cell phone + Dongle on the drone itself or with RC Pro and Dongle + Dongle on the drone (2 dongles). I have Verizon cellular provided, which is CMDA + LTE 4G.  Wonder if anyone got it to work and also with Verizon or maybe a different cellular carrier, am open to getting an extra line with another carrier if needed.

I’ve used it with my Dji RC Pro only so far and the Internet to the the controller works flawlessly. Just received the second 4g lte Dongle and mount. I’m not sure about the laws in the US as of yet for BVLOS but definitely like to hear from DJI before I test it out

Mrwoods6679 Posted at 12-7 21:42
I’ve used it with my Dji RC Pro only so far and the Internet to the the controller works flawlessly. Just received the second 4g lte Dongle and mount. I’m not sure about the laws in the US as of yet for BVLOS but definitely like to hear from DJI before I test it out

Hi Mrwoods,

   I've also had success with using the 4g lte dongle with the RC Pro. The issue is with using it on Mavic 3 and attaching it to the drone and connecting to the USB-C port in the back. It seems the dongle is not permitted and locked against usage in US region. Would leave it to DJI / others to answer your questions regarding BVLOS.

Thanks, Mike.

Is the 4G dongle for the Mavic 3 work in France and where I can buy it ?
Thank you for your help.

Tony64 Posted at 2022-3-26 15:11
Shafted by DJI again, the list is never ending, confirmed non working in the UK I love this drone, but feel like its full potential will never be fully released.

Have you tested it by blocking the signal from the RC to the drone, i.e. see the drone outside and take the RC inside so that you loose transmission to the drone, see what happens as i am very interested in the Dongle for the UK too

Was a lot smarter for DJI to provide a dongle with SIM CARD that can work in 4G with standard operators from common countries and directly connect to phone as a direct link using phone numbers, and not to go through DJI servers. In that way could be sold everywhere.
There is nothing to do with BVLOS in different countries, as this is not for BVLOS, but a safety feature in case you get a tree or any object in front of RC and loose signal. VLOS can be achieved with an observer.
The issue probably was that was using Chinese servers, meaning that all video goes to China....and this is not something that you really want in some country.... hell, I don't want it either, even if I am open minded.

I have the Mavic 3 enterprice, with rc pro controller.
Living in NL, the controller works with 4g data sim card (simonly)
The dongle on the mavic is green lighting but get NO transmission update.
Try with VPN on Australia - Rusia - HK but not working

https://youtu.be/2IO1JJdKNOA

한국에서  되는 dji lte dongle

https://www.dji.com/rc

Is it possible to use cellular mode with the rc controller linked above? As you know, the mobile data feature came in the latest updates.
Question 1: Will it work if a dji 4g dongle is plugged into the usb c port?
Question 2: Is it possible to communicate with the drone via rc control phone cellular (like as  rc-n1 to drone cellular connection)

Notes: My questions are not for rc-n1. I know it works for rc-n1. (only asking for rc controller)

zern Posted at 1-30 13:09
https://www.dji.com/rc

Is it possible to use cellular mode with the rc controller linked above? As you know, the mobile data feature came in the latest updates.

It's not what you're using; it's where you are. 4G cellular transmission is officially 'China Only' at the moment. Anywhere else in the world the 4G dongle provides nothing more than a 4G internet connection to the RC Pro or the DJI RC.

Raf_IZ0QWM Posted at 2022-2-23 21:32
https://bbs.dji.com/forum.php?mod=viewthread&tid=294747

How can I view your forums ? I have the DJI mini pro three with the RCA remote if I want to get the cellular module do I just need it for the remote and the Sim card or do I also need the bracket that attaches to the drone and then wires in?

Monkey007 Posted at 1-30 15:28
It's not what you're using; it's where you are. 4G cellular transmission is officially 'China Only' at the moment. Anywhere else in the world the 4G dongle provides nothing more than a 4G internet connection to the RC Pro or the DJI RC.

The dongel work in turkey