A5c Low PHy Rates


#1

Hi All,

We have recently begun testing our wireless service on our tower locations.

Our first day of testing we had some issues with Low Phy rates from the A5 to Client, but yet the Client to A5 was getting 200+. I have attached some screenshots of our current config. Just wondering if anyone has any suggestions for long range setups for the A5c. FYI These are all Fibre fed and each panel will have 250 mbps of bandwidth to start with.

Also the Antenna we are using with the A5c is the 5 GHz 17 dBi (4-Port) Dual Pol H/V 65 Degree Sector Antenna. KP Antenna Page

Here is the Antenna I am using along side the Mimosa C5c Radio for our CPE Device:

MTI 24dBi Antenna

We are looking to provide packages of 25/10 (being the max speed) in a radius of about 5 kilometers.
So any suggestions would be great. Thanks!!


#2

Mind you, these tests were only from about 500 meters away, I am worried that we may not be able to achieve our speeds with these PHy rates. Correct me if I am wrong though. Thanks!


#4

So, I am doing that with the exact same hardware, but in a pretty rural location and with people significantly farther.

Looks to me like you have noise that the C5 can hear but the A5 does not. (Which is why you have significantly higher throughput to the A5 then coming from it. I would check the Channel & Power page on the C5. (The Combined option on the A5’s Channel & Power page shows noise from all connected clients.

Another issue could be antenna height, I have a customer about less then 500 feet from my tower (which is 140 ft) This customer has always been a pain because the signal chains can’t balance very well. Unbalanced chains will very negatively impact your total throughput. It is good to keep them within 3 dB, but if you can keep them under 1 dB difference life is better.

One trick Mimosa Support showed me a while back was to Manually set the AGC. When it is in Auto it can take 5-10 minutes for your throughput to actually hit maximum after connection. What you do is change AGC to Manual then drop it down until your weakest client either starts to disconnect or disconnects. Then you drop it 2-3 dB. Has improved overall throughput on my sectors 10-20% by running it manually.


#5

If you wanted to stay in an 40MHz channel, it looks like around 5580 is a better choice than your current selection. William is probably dead-on here when he mentioned interference on the client side here. In some of the shots, you can see that your SNR is only just above 20. Really a solid connection needs 28+ SNR on both upload and download.

You could also try using a 20MHz channel, depending on the speeds you want to offer to customers. I find that with a 20MHz channel, I can safely provide 60d/60up speeds to all customers connected.


#6

Hey guys, the feedback is greatly appreciated. When I go test tomorrow I will adjust settings accordingly and see for better results! Thanks!

Just curious though has anyone used the C5c with the MTI antenna before? Is there a different antenna I could try as well ? (I know its un related to the problem, but just wondering what others have been using)

I will reply again by the end of the week with my results. William5, have been an absolute life saver not only with this issue but previous questions and problems before. Greatly appreciate your feedback!


#7

@Connor

No problem, I do it for the fun and my own learning on Mimosa Equipment. (Most of my answers are just me running to the manuals to see what they say about the problem.)

Could you link to the MTI antenna? I have used at least a half dozen different antennas with the C5c, I have a post that a couple people commented their experiences with a few different antennas.

I would say that for your distances there are plenty of options, but I would go for the C5x if you can get them. Significantly cheaper for the overall package (Radio + Antenna) then most antenna combos you can setup for the C5c. (And you don’t have to worry about pigtails, mounting, tools and all the other BS that is just a headache.) Being limited to 100 Mbps Ethernet is not going to be a problem for you and even if you do end up upgrading, you are still reasonably priced compared to the C5c.


#8

Hey all,

Had some better results in the field today, just curious about one thing;

the Client to A5 RSSI seems to be okay, but the A5 to Client appears to have an issue, could this be due to high gain on the A5 side?

Here is a screenshot:


#9

@Connor, I normally only see signal missmatch like that when an antenna has been improperly programmed for it’s antenna (ex: a C5c that has a 25 dB antenna, but is programed with a 10 dB antenna thereby making it go over EIRP while the A5 wont.)

This doesn’t look to be the case here, but I dunno. What were your signal chains on the A5 and the C5, could be you were on a side lobe on one side or the other. (or both.)


#10

Hey Gents,

I am curious about one thing, I have been asked to inquire about how we currently have our channels set up. I chose the active channel for each AP based on the lowest noise level I could squeeze into. I am wondering if you think using the same or similar channels (even though the spectrum analyzer appears to look okay) will cause issues? I don’t see many other options to use as opposed to our current set up. By all means correct me if I am wrong.

Here are the panels as shown.

EAST PANEL:

NORTH PANEL:

SOUTH PANEL:

WEST PANEL:

Also just for shiz n gigs, here is a picture of the tower just so you are aware they’re not all on the same pole or something crazy like that:


#11

you mean like this?

Here is another post where I explain the picture and some other people chat about options when limited on space:

I have the freedom to not have to reuse channels, as well as some frustrations that seem to be isolated to my first Mimosa tower. So I do not reuse channels, but when I have it works better then other equipment I have used.

The largest concern is that you need to make sure that the CPE cannot hear the other A5s very well. This document will explain the issues involved in depth:
http://ap.help.mimosa.co/gps-sync-spectrum-reuse-gigapops

I would recommend keeping a close eye on the noise your A5s are hearing. As you add more clients is where you will start getting intermixing of the noise and could cause troubles.