Other user interferance

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Hi, I was wondering if there would be an issue if another operator was to set up & begin flying his drone - in theory within the 7km radius of me - or visa versa, in the same area as I was already in with mine?
I will soon have my hands on a DJI P4 & hope to use it at some of our local beaches & headlands, however I have seen another person in recent times set up there also.
Once a connection is made by my remote to the drone does the signal remain unique to mine only?
 
Yes, the remote is paired with the drone that you have. You don't have to worry about your signals getting crossed. If you can find a buddy you can stand side by side and fly together, each with their own drone.
 
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If 2 RC are ON in the same time at a distance closer than 50ft, interference WILL occur. Is not about the RC to drone pairing, is all about RF waves and signal interference.
By the low of physics regarding RF, two waves of the same frequency will cancel eachother.
 
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If 2 RC are ON in the same time at a distance closer than 50ft, interference WILL occur. Is not about the RC to drone pairing, is all about RF waves and signal interference.
By the low of physics regarding RF, two waves of the same frequency will cancel eachother.

Oh ok, at 50 feet it will be pretty obvious there is another operator in the area.
I was more concerned with not seeing the other person & affecting his flight, or him affecting mine.
Cheers ; )
 
If 2 RC are ON in the same time at a distance closer than 50ft, interference WILL occur. Is not about the RC to drone pairing, is all about RF waves and signal interference.
By the low of physics regarding RF, two waves of the same frequency will cancel eachother.

A month or so ago a friend of mine was flying his P3 while I was flying my P4. He moved closer to me within a few feet and it clearly caused interference with my signal. He moved away 10-20 feet and all was well again.


Sent from my iPad using PhantomPilots
 
If 2 RC are ON in the same time at a distance closer than 50ft, interference WILL occur. Is not about the RC to drone pairing, is all about RF waves and signal interference.
By the low of physics regarding RF, two waves of the same frequency will cancel eachother.
Actually Danny, I believe it is two inverted waves that will cancel each other out.

Sound is a pressure wave, which consists of alternating periods of compression and rarefaction. A noise-cancellation speaker emits a sound wave with the same amplitude but with inverted phase (also known as antiphase) to the original sound. The waves combine to form a new wave, in a process called interference, and effectively cancel each other out – an effect which is called destructive interference.

I only know this because this is what noise canceling things like headphones do. They use a mic to record the audio and in realtime they invert the waveform and two exact opposites, cause noise cancelation.

I bask in your knowledge D, but I'm fairly sure on this one.
 
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If 2 RC are ON in the same time at a distance closer than 50ft, interference WILL occur. Is not about the RC to drone pairing, is all about RF waves and signal interference.
By the low of physics regarding RF, two waves of the same frequency will cancel eachother.
Agreed however of little consequence here. The RC's will behave like Wifi routers to play nicely and share the available spectrum to avoid using the same channel.
 
Actually Danny, I believe it is two inverted waves that will cancel each other out.



I only know this because this is what noise canceling things like headphones do. They use a mic to record the audio and in realtime they invert the waveform and two exact opposites, cause noise cancelation.

I bask in your knowledge D, but I'm fairly sure on this one.

You are 100% right, two RF waves of the same frequency, amplitude and polarization, one of them defazed 90deg will cancel eachother (from a sinusoidal wave will become a flat line, kind of). In the case of two RC that are ON in the same time close to eachother the Rx signal will encounter interference. It is more like you standing in a spot and have two guys left and right of you ( O...X...O ) yelling in the same time in your ear making it hard to understand what they say. The video on the pad will be OK, go to green, have lines through, be OK, have pixelation, be OK, go to green, and so on. Once the RC are separated by at least 50 ft the video will be fine. Same problem if you sit down in the shade of a truck at a distance closer than 4ft, the Rx will hit the RC but in the same time the same RF will travel past the RC, hit the truck and reflect back to the RC causing the same type of interference. Have done it many times hiding from the AZ sun...
 
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You are 100% right, two RF waves of the same frequency, amplitude and polarization, one of them defazed 90deg will cancel eachother (from a sinusoidal wave will become a flat line, kind of). In the case of two RC that are ON in the same time close to eachother the Rx signal will encounter interference. It is more like you standing in a spot and have two guys left and right of you ( O...X...O ) yelling in the same time in your ear making it hard to understand what they say. The video on the pad will be OK, go to green, have lines through, be OK, have pixelation, be OK, go to green, and so on. Once the RC are separated by at least 50 ft the video will be fine. Same problem if you sit down in the shade of a truck at a distance closer than 4ft, the Rx will hit the RC but in the same time the same RF will travel past the RC, hit the truck and reflect back to the RC causing the same type of interference. Have done it many times hiding from the AZ sun...
Dang you're smart. I am just glad I can hang in the conversation. LOL!
 
I want to make public that I am a PIMP!. I have been trained, licensed and went PIMPing many times...:).
Passive (reaction is due to your action, such as flashing a light into a mirror and the light blinds you)
Inter (between two fixed units)
Modulation (manipulation of a wave form)
Protocol (the reason why it happens)
I have worked in the cellphone RF field for over 19 years and many times we found the cell blocking (no Tx/Rx) due to passive interference (sent wave is reflected back to the transmitter causing RF noise, wave deformation, signal degradation) such metal, water, trees in the way of the RF signal. Signal interference should not be confused with signal cancellation. DJI drones work on the same principal of Tx-Rx and are just as much susceptible to RF interference and degradation as any unit working based on wave signals.
Best method to avoid RC interference is to have a clear line of sight (even at long distance between RC and drone), keep distance of two RC working in the same time, stay away from any metal that could reflect the signal back to RC.
As RED said: Ya, I know, I'm ugly.

pim.PNG
 
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I want to make public that I am a PIMP!. I have been trained, licensed and went PIMPing many times...:).
Passive (reaction is due to your action, such as flashing a light into a mirror and the light blinds you)
Inter (between two fixed units)
Modulation (manipulation of a wave form)
Protocol (the reason why it happens)
I have worked in the cellphone RF field for over 19 years and many times we found the cell blocking (no Tx/Rx) due to passive interference (sent wave is reflected back to the transmitter causing RF noise, wave deformation, signal degradation) such metal, water, trees in the way of the RF signal. Signal interference should not be confused with signal cancellation. DJI drones work on the same principal of Tx-Rx and are just as much susceptible to RF interference and degradation as any unit working based on wave signals.
Best method to avoid RC interference is to have a clear line of sight (even at long distance between RC and drone), keep distance of two RC working in the same time, stay away from any metal that could reflect the signal back to RC.
As RED said: Ya, I know, I'm ugly.

View attachment 66928
PIMP, cool- LOL

At least in digital data transmission most of the subject issues present less of a headache. This is especially true with DJI's implementation of MIMO and OFDM with no TX end EC required on the video downlink.
 
I wondered (played the game in my mind) what if both antennas are connected to the Rx port on the board? At lease there will be a bit of Diversity Rx and could improve the video reception.
Those of you that modify the RC units, find a way to split the Rx cable and take one of the antenna wires to left antenna. I know, it implies a lot of work but rigging a wire on the outside will produce the intended goal. In the end you want to have 2 Rx antennas as opposed to only one. Cell towers have 4 antennas for Rx named 4-way Diversity Imbalance.
 

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