A5c 40Mhz Question!

@Jaime @DustinS

Good Morning
Dear, we have several AP A5c, with omni 360 antennas and others with 2x2 sectors.

All the CPEs are C5x, with Horn of 16. maximum distance 2km.
Now that I tell you how our distribution network is set up, I am writing to you:
The query is how many Mbps can an A5c deliver in 40Mhz with all its cpe negotiating well?

Our reality is that it does not exceed 100Mbps, and i need at least 140Mbps.

we do not want to change to 80Mhz since we are with little and no space in the spectrum.

Thank you in advance for the suggestions that you can give us.

Iam Testing Firmware 2.5.3-beta8 (A5c/C5x)

There are plenty of people who have posted ~200 Mbps on a 40 MHz wide channel.

That said, you need your clients to have pretty good connections, +26 dB SNR for you to see that. Could you post a picture of your Clients PHY Stats page? That would help for pointing out where your issues could be.

If you post a picture of your Channel and Power Page I might be able to make some recommendations for tuning your radio as well.

Thanks for your reply,

Ok a few things:

  1. This AP is already running 80 MHz. Though some clients are only able to connect at 40 MHz.

  2. Your DL SNR and UL SNR are very frequently not high enough to perform well. Check out this link: http://ap.help.mimosa.co/access-point-faq-snr-mcs

  3. Because your SNR isn’t very good, your AP is unable to “talk fast enough” to send data at higher speeds (By using higher MCS rates) Imagine your AP is in a crowded room, it has to talk slower to be understood by your CPE equipment. Some CPE equipment is closer/has a better connection so they have better SNR numbers and therefor can talk with the AP faster (Higher MCS) and therefor the AP has to spend less time talking to them.

Here are a couple more links explaining in more detail what I am talking about:
http://ap.help.mimosa.co/access-point-faq-sensitivity-for-each-mcs-index
http://ap.help.mimosa.co/access-point-faq-evm

  1. I would drop your channel width ddown to 40 MHz, that will help increase your SNR and avoid a bit of noise.

  2. Next I would Manually Tune your AGC level on your AP. Here are some good directions for this: http://ap.help.mimosa.co/srs-tuning-agc

After all that, My next step would be to recommend higher gain antennas as well as smaller sector antennas where you can afford it. I would consider the N5-X25 antennas for your C5x CPE radios, that will help a bit. Mimosa has N5-45 antennas that have really good performance. Where you are at, the noise levels are pretty bad, so I would look to those or RF-Elements Horns. Those will be costly and require extra APs, I feel your pain I am having to do the same in my network to increase my performance. The costs are well worth it though, I have increased the throughput of my APs by 20-50% just by doing this across my network.

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You will only see those speeds with low client counts and clients with max mcs numbers. You need to swap out that omni for a narrower antenna to get a cleaner spectrum. Also try using the clear spectrum above 6100 MHz.