From the creator of "Let’s improve this 45Km Link!" comes.. "Let's push this 56km B11 Link to the limits!"


#1

Hello everybody, long time from my last post and last use of the Mimosa technology.

Today i bring a new link made with the B11 products, a 56km link that is working excellent for us and another link i want to put in the table for discussion and possible improvements.

The antennas we are using are the 1200 Jirious model.

We are using the firmware 1.4.0 - 12, i will upload some images with a lot of data on the link in the order i will detail below and in a second post i will make some questions about possible improvements.

B11 AP SIgnals
B11 AP Streams
B11 AP Config
B11 Thoughput and latency stress test

Then i will put images of 1 week data collect of Signal, EVM, PER and MCS-STREAMS






Any success stories with B11 links ... looking at 9.5 miles?!
#2

Now the questions to open the discussion and see what could be improved.

  1. The signal has 10 dB Jitter or more with no reason (no heavy rain, fog, snow or anything)
  2. I have configured the link to manage the MCS Rates accord to PER values and a Conservative method, Why they jump so much up and down? is this because of the Signal issue in point 1?
  3. Why the EVM could be so unstable? it has any relation with PER? because PER values are excellent as you can see in the one week data image
  4. With those excellent SNR values i cant push the highest MCS rate with any configuration (i have tried 8ms in TDMA, agressive rate selection and bot PER and EVM rate selection method. Is this a limitation in the link distance?

Well the post is open and I appreciate any opinion or take any questions.

Bye!


#3

I am impressed on this! We just licensed a 17 mile link (27 km). To get the proper “Full time” throughput we are looking at, we decided that an 8 foot (2.4 mtr) dish was needed at one end (where we had a large tower to hold it). We are going to be using the Jirous 1200 dish at the other end.

This allows us to turn down the Transmit power, and we should be able to then obtain the full MCS 9 connectivity rate full time!

You might, just for a test, turn down the TX power and see if the MCS rate will then go up to MCS9?
Try it 1 Db at a time, and watch the connection rates!

I was wishing that we could get more throughput in one direction, maybe need something more than 75/25, maybe 90/10 (If that was possible)?


#4

Hi Wayne

I’ve tried turning down the TX power but with no better results. I’m starting to think that there’s a distance limitation… some mathematic about times and ACK…

I installed the latest beta version of the firmware (1.4.1) about three days ago with excellent results, now i get more stable MCS rates, i will upload new screenshots of the link this week.

Maybe some techs of the Mimosa team could tell me if the distance could be a limitation on the MCS rates selection.


#5

Hi Luis,

Here are the distance limitations for fixed TDMA modes:
2 ms - 32 km
4 ms - 64 km
8 ms - Distance limited only by Free Space Path Loss

A message is displayed in the GUI with this same information upon making changes to the TDMA Window (Wireless > Link > TDMA Configuration).


#6

Hi Chris

I understand that, i configured the TDMA in 4MS and tried also the 8ms one. my question is if theres any limitation in MCS rate selection that has something to do with the distance.

I have the necessary SNR, PER and EVM to connect in MCS 9 but i only get MCS 7, i thought this is something related maybe with distance.

Why do you think i could be limited to MCS 7 Rate?.


#7

Hi Luis,

FSPL would further limit SNR and therefore MCS. Aside from that, we have also limited MCS in Rate Adaptation to maintain very low PER. Firmware version 1.4.1 contains controls for this (Wireless > Link > Rate Adaptation) that allow higher MCS if you are willing to tolerate higher PER: http://backhaul.help.mimosa.co/backhaul-ug-rate-adaptation


#8

I have PER rate selection and Aggressive mode, i got less than 1% PER and EVM is below -22Db

What other factor could compromise the link to not obtain higger MCS


#9

Here are some new pics with the 1.4.1 Version, i can’t see any other thing to not obtain higer MCS


#10

Hi Luis,

Please set Rate Adaptation Criteria to EVM and let us know the result.


#11

By the way, you can reach Mimosa Customer Support directly through one of the following channels:

  1. Chat with us directly from 7AM to 7PM PST at http://help.mimosa.co
  2. Send email to support@mimosa.co

Chat is especially useful, because we can help you tune a link live via screen sharing.


#12

Hi Chris, I listen to you and i just ended an excellent support sesion with David Dippon. We made to the conclusion that everything is configured perfect and that all the values are excellent (PER, SNR, EVM) but we cannot pass the MCS 7.

He ask to give you guys public access to the link so you could analize it in a deeper way, but i have this link on production so David is going to discuss this case with you. I’'l try to help in any other way i could.

I want to make clear im not complaining about the link, for me is working excellent i have a total throughput of almost 1Gbps with excellent stability. I just want to help and share all this info with all to improve our links and push them to the limits

Best regards


#13

Any updates on this thread?

How is the link preforming?

We are looking at a 42km link with the 1.2 meter dishes trying to decide on the Mimosa B11 or to wait on the AF11x

Thanks,
Kingsley


#14

Hi Kingsley

The link is performing very good, it has one only problem, it doesn’t reach the MCS 8 and 9. Mimosa’s engineers are working on the link for about a week searching for the possible problem.

Taking that away, the link is giving almost 1gbps of traffic (we are splitting it 75% 25% to achieve 750Mb + 250Mb) and is working great for us. The second post that contains a lot of images shows the perfect condition of the link.

I never used the Ubiquiti AF11X but i’m very pleased with Mimosa’s equipment and support.


#15

Luis,
can you post a screenshot of your Wireless “Channel and power” page?

Noticed that the “target” is -49, and you are getting -45. Could be that you need to adjust your antenna gain a bit, so the radio calculates correctly, and that might allow the MCS 9 to work? Try to get as close to the target number as possible using the antenna gains, and the TX power.


#16

Hi Wayne

Thank you for your time and for the tip, i have Mimosa’s engineers working on the link for about a week now. It’s seems that the problem is a tricky one. When they finish their job i will post new images with the final results.

Best regards


#17

Hi Luis,

Yes please any info you can provide would be greatly appreciated. We bit the bullet and ordered the B11 which we will have in our hands start of September. Then we will be making new mounts to get it up around mid September.

With some luck Mimosa will have the kinks sorted for long links as our one is 42km and looking for max bandwidth.

Thanks,
Kingsley


#18

Consiguió usted mcs8-mcs9?


#19

Hi Everybody.

Sorry for my absence. We obtain maximum data rate and an awesome throughput of 1300 Mbps!!! (1Gbsp Down 300Mbps UP) with the 75/25 feature.

I show you a picture of a 53Km running link


#20

Very nice! Are you running different firmware now, or was just antenna missalignment?