2x RB411r w/ Mikrotik 900mhz radios, 1/4mi apart...bad SNR

Hardware MikroTik hardware general
1

I’m pretty okay w/ networking, but a noob at tweaking a point-to-point radio installation.

Equipment:
2x Routerboard 411r controllers each w/ a Mikrotik 900MHz radio @ 20ft
2x 3Com 4-port 10/100 switches
2x 12v 3A PoE injectors

Cable length from injector to radio is 30’. Both panels are 1/4 (.25) mi apart shooting through moderately thick groves of pine trees. One panel is 20ft up a 95’ radio tower. It can be raised to 80’. Other panel (my house) the panel is mounted on 10’ of mast next to the upstairs-bedroom window. Using WDS bridge (tried EoIP tunnel but they wouldn’t associate w/ each other).

I used GPS to aim them at each other. Plot 1 in front of my panel, plot 2 in front of antenna on tower. They are dead-on aim-wise and at the exact same height.

SNR is -80, Overall Tx CCQ varies between 95% and 100%. Noise floor is -87.

I feel my SNR could be better, and the noise floor could be lower since this is a relatively remote-location install on top of a small mountain. I have neighbors, but were spaced pretty far apart so I don’t know whats up w/ the noise floor being as high as it is. Is that a normal value for the noise floor?

Also, I looked a little and probably could have searched more…but I don’t understand what an “overall tx ccq” is.

I’m extending a wifi-broadband link from the antenna on my neighbors tower (my antenna, his tower) to my house. Its a 3mbit plan, and I get all 3mbit (sometimes a little more) and an average ping from Maine->NYC of 20ms. When I do a continuous ping to google.com it stays between 15ms and 25ms…but has occasional fits of 150ms - 300ms. The climax of the ping fits usually consists of 4 or 5 failed pings, and then back to normal. I’m wondering if a better SNR would help with this.

Short version: I’m wondering if my noise floor should be better, wondering what “overall tx ccq” means, and wondering if a -80db SNR could be the cause of occasional fits of network lag and unreturned pings.

Thank you!

PS I bolded what I suspect are negative factors causing the bad SNR values.


EDIT: I think its also worth noting the TX-rate hops around quite a bit. It usually hits all of the values (1, 2, 5.5, 11) and not in order. It doesn’t build-up to 11 and go back to 1…it just hops around. I’ve tried turning the panels slightly to find the best average SNR, but they always end up back where they started. I think its the trees.

2

SNR of 80 is severely overpowering the link. If it is actually showing -80, then something is wrong with your Routerboard.

Or do you mean your signal strength is -80dB? Signal to Noise Ratio or received signal?

3

sorry..signal strength is -80 as read in the “Registration” tab of the built-in web-portal on the radio.

I’m also at work at the moment. I’ll update this thread w/ a cut/paste so that my horrible misuse of terminology doesn’t interfere.

4

wlan1 00:15:6D:xx:xx:xx yes -81 11Mbps-SP

On the registration page its labeled “signal”…so yeah. My signal is -81

5

After you aimed with gps did you the fine tune the link? Also at a 1/4 mile your fresnel zone is around twenty feet so any little hills in between your house and his will directly block the link. Definitely raise the tower end as high as you can and have another person watch the signal strength while you VERY slowly turn the antenna

6

Yeah I did. -79/-80 was the best I could do.

That said, on the internet side I’m on my own radio now, and all of the ping issues are gone. I was previously sharing w/mu neighbors home network so I suspect now (after w/ talking to a guy I work with who is godly at this stuff) that the ping shenanigans were more due to his family ramping up what they were doing online. Now that i’m on my own outside connection things are great.

I’ll worry about the tower-panel this spring. Even w/ -80 signal I’m seeing 20ms and full bandwidth w/ no drops so I’m going to leave well-enough alone for the moment.