Multiple pilots using FPV simultaneously

[thavermin]

I have been trying to search for a definitive article explaining how to best have multiple people using 5.8ghz FPV signals simultaneously but I can't find anything that explains it properly.

I want to have 4 users simultaneously on 5.8ghz.

The original solution for 3 users (all using fat shark bandwidths) was channel 1, 4 and 7. I figured that this would give the greatest distance between signals. Unfortunately we had major signal issues with channel 1 and 7 getting intermittent interference from channel 4. Sometimes receiving channel 4 video signal instead of our own channel.

After some thinking and a bit of research we figured that because channel 4 is 5800mhz and our tx and rx are tuned to 5800mhz - then anyone transmitting on this band would be sending a "stronger" signal which may override anyone on say 5860 or 5740.
This issue only presented itself when there was 3 people. In any combination of two people there was little to no interference. If I went up using 5740 with my friend using 5800 we had no issues. As soon as we included the third person then channel 1 and 7 had signal loss.

We have since purchased 32 channel vtx's but two people are still using fat shark attitude V2 goggles which (I believe) only receive on 7 channels. Our new idea is to have the two fat shark users on channels 1 and 7 (5740 and 5860), whilst the two 32 channel LCD VRX users will take the highest and lowest bands (5945 and 5645). This puts a minimum of 85mhz between each user and also distances us from 5800 as much as possible using fat shark frequencies. However we are yet to test this.
My main concern other than signal interference is that the further from 5800 we get, the less efficient the antenna's will be.

Has anyone found a solution to this sort of problem. If so can you explain it or link an article that can explain it.

 

[GJH105775]

1,4,and 7 are what most people do, if you could use different bands that would be great, but may not help too much. One question, how close are you guys standing together when you do this?

 

[thavermin]

When there are two of us we usually sit a few feet apart with no problems. When we tried three of us, we did the same and had major interference problems. So we split up to different parts of the track. This worked better for me as long as my quad was the nearest to me, but as soon as it was further away than another quad (especially the quad transmitting on channel 4) then signal interference returned. The whole time channel 4 appeared to get no interference from 1 or 7.

Just went out yesterday and did some testing with two of us flying. I chose channel E8 5.945ghz while my friend chose F4 5.800ghz and I had no signal problems regardless of where we were in relation to the quads. This has confirmed that the 5.8 tuned antenna are capable of sending and receiving a wide range of frequencies and that using the more distant frequencies is an option at least with two people on 5.8.

Id consider using 2.4ghz for FPV if every person didn't have a 2.4ghz radio transmitter. 1.3 and 1.2 have antenna that are just far too big and vulnerable to damage in a crash. Really need to find a solution or at least reach a conclusion with the limitations of 5.8.