Weird MCS Levels

Hi everyone,

We have a few client´s with some weird MCS level´s on the downlink, normally the rssi level is -72 and -69 and some of them have MCS downlink 1 and MCS uplink 10, so i was wondering maybe it got something to do with the perfomance of the antena.

We use an ePMP 2000 with antenna 90/120 with mounting kit, so could you please tell me what cause the MCS of the downlink get poor level´s when the rssi is good?

FYI... lower numbers for RSSI are better then higher numbers. -72 is OK... but not a great signal. Having a -60 for instance would be much better. ALSO, take a look at your SnR values for these problem clients. Where are they at? With SnR, higher numbers are better.

If it's just a couple clients having issues on a sector with many good working clients, you might want to consider increasing the gain of these problem clients, by installing F200's, along with seeing if you can turn the AP's TX power up any higher. Depending on your region and/or band, e2k's can transmit up to 30dBm. In addition, you could try reducing the channel width, you can get additional gains. Each channel step down gives you about 3dBm more power, and if there's a lot of noise in the band, using a smaller channel width will help increase SnR.

Ok, thanks for the response, here are the information of one of the clients:

Btw, the equipment is one of the oldest 5Ghz integrated radio, this could be the problem?

This is the other from the same sector and this one had good levels of RSSI and SNR

Yikes, you're using one of the orignal integrated radios? The ones that look like this:


I would swap this out with a Force 180 or 200. All these first gen integrated models were discontunued long ago... partly because their antennas are not very good.

Two other things I forgot to mention... have you tried using a different channel or channel width? And secondly, if you run an SA or eDetect on the client, are you seeing any local noise?

Yeah that´s the famous one, thank you we are gonna change that inmediatly,

i try with e-detect on the second client and didn´t show any local interference, so i will try to change the transmiter power and gain on AP, also we are gonna update the firmware of the SM.

Thank you so much for the help.

I'd def upgrade everything to the newest stable revision, which is 3.5.6... it's working very well for us, we have it deployed on hundreds of radios.

Let the group know if there was any improvement after the suggested changes! I'm curious to know. Good Luck!

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