A5C / C5X P2MP -- mixed bandwidth possible?

Is it possible to have mixed bandwidth when using this combination of radios?

The A5C uses N5-360, and the C5x uses N5x25 antennas.

I have one location, at the edge of the 4km reach that I can only provide service if I use 20mhz, and that’s fine, but ALL my other end points are much closer and can gain from using 40mhz, and even 80, but that’s not in the plan.

So, I’m wondering can a single client be limited to 20mhz while the main site is set for 40mhz? Without having to install another radio/antenna at the base site.

Supposedly this works. There are users on the forum (notably @Rory) who use 40-80 MHz wide channels all the time for their customers and have great success.

I tried it on one of our APs and it caused issues with clients that would jump between 20-40 wide channel widths constantly and caused short connectivity issues for the customers on the AP. That said, I had pretty poor connectivity on that AP and lots of customers that were +5 Km away from the AP. Then again that was a few years ago, now I have moved the further customers to different APs and upgraded connectivity and am running a 40 MHz wide channel with good results. So just keep in mind that it “can” work, but you may want to keep an eye on the situation and make certain that you don’t run into issues.


Well… I did speak to support. They advise, at least in the combined A5C & C5x P2MP implementation, that it’s not possible to have different client bandwidths in the same AP.
Now, this stands to be true in that the AP drives the end point C5x client connection to whatever the AP is setup for.

So, if possible, then I have no details on how to even implement it for testing.
The C5x shows a field of “80mhz” max bandwidth…Well, I knew that was the max, I want it to be 20mhz max, not 80! :slight_smile:

The only way I can tell to go mixed would be multiple radios to account for the different bandwidth needs. There is no perfect setup, only compromises…unless maybe one has really really deep pockets!

Also, support told me that my 4km link shouldn’t work at all… well… sorry, don’t tell the radios this, cuz it works very very solidly using 20mhz, and it beats out a commercial WiSP that’s also feeding the same end point with its own link. (Cambium setup apparently)

@William5 - thanks for the link to faq’s… That’s a great set of charts to have handy.

On the point of the Channel automagic I would differ to Mimosa support, when I run a 40 MHz wide channel (which is rare for how far out most of my customers are) I only allow customers onto those APs that will have really excellent signal strengths.

I don’t think there is a manual way to force an Client to stay at 20 MHz, otherwise I would be using it.

This industry is rife with compromises. Cost being one of the biggest ones you have to deal with. I could build a really cool network that would blow the socks of most anyone, but it’d cost so much I wouldn’t have many customers.

I will call BS on the 4 km stuff, you won’t have an awesome link, and it requires a lot of maintenance to make certain thinks are working well. But I have plenty of happy customers on a 20 MHz wide channel N5-360:
Now, I don’t sell my highest plans to these customers and I am pretty much in the middle of nowhere and the only noise I really need to compete against is the noise from my own APs, so my situation isn’t applicable to most people, but it is possible. (Just don’t count on it unless you know what you are doing or willing to suffer through the pains of learning)

Unclear about your reference to 4km and calling BS – No BS from here – running solid for almost a month now and that includes some seriously heavy rain that came.

In our case, the services are not for public consumption. These are for multiple clinics where we control everything and they have no say. This specific link is a (squeaky wheel) installation, and it breaks all of our usual models. So, I’ve been pushing all the limits to get a full understanding, or at least a lot better understanding of our environment and how potentially stretchy it could be.
We’re rural, so we appear to be similar in the basics of the RF side of things that can get in the way, although I suspect you’re more rural than we are.

The 2 spikes are our co-located B5 back hauls, so, we’re our own enemy as well at least on the tower.
From the client end…basically crickets…

As William was saying, let the AP figure out the channel size if the client can’t use the full size spec’ed. We have always set and designed for maximum size, right now 40-80MHz depending on how many clients and speeds. There is no substitute for s/n ratios being wigged so always engineer for your maximum channel width but if the channel gets interference, use auto-everything and let it figure it out. We have had great success with it.

I think my original questions went off on a tangent unintended…

That being said, since the AP controls the client, mixed bandwidth isn’t an option. None of my implementations have ever chosen something on their own, so if they were intelligent enough to drop from 40mhz to 20mhz, they don’t… all locked in from the AP.
My query was to see if with this particular setup, having mixed bandwidth at the client end with the single AP was a remote option, and it appears that is a big nope.

Thanks all for the great info and input.

Yea, I think we are talking past each other here. I’ll try to explain this further. You design for the channel width you want. That’s set at the AP. You set the clients to a maximum of 80MHz. During operation, if there is interference or some other reason that the AP or the client are having trouble, not only down to the channel width, but on each of the two streams, the chipset will actually change the channel size dynamically to maintain the connection according to which protocol option you want. You may see the horizontal upload drop to 20MHz but the vertical link stays at 40MHz. This is part of the beauty of that particular chipset.

I see what you’re saying… I wasn’t aware of that flexibility of the chipset. I was able to find some details, but this wasn’t one of them.

I have to say though, I’ve been working with “wireless” since before it was standardized, and so much of what I do NOT have to do these days because as there was a commercial years ago… It’s in there!

My design was meant for 40mhz, and then the squeaky-wheel got tossed in, so to satisfy that part, I’m only left with 20mhz, or to change my antenna system to sector antennas. I may still have to do that, but for now, I’ll work it from the N360 angle since reality is I have more clients properly handled there than just one. Unless it’s the boss, and maybe not even then, you don’t change everything for a single end user. Money is a limited resource that’s hard to come by.

Understand. The noise issue is why we have moved to A5x radios and RF Element horns. Massive improvement over sectors with wider beam patterns and a better s/n ratio than wider sectors with 4x4. Had to put up 2 more Ultrahorns today to take over for the noise a 30degree sector was picking up.

@Bryan3, I was referring to Mimosa saying that 4km was not doable on the A5c with the N5-360 antenna. As I posted, I have many people (pictured) that are well above 4 km distant from the AP and working just fine.)

AH HA! I have some snow today and one of my customers on one of my 40 MHz wide channel APs did it!

AP is set to 40 MHz, 31 other customers are transmitting back to the AP at 40 MHz, but this one customer is dropping down to a 20 MHz wide channel (probably a mix of reasons) for transmitting back to the AP. I would bet if the issues were bad enough that the AP would use a smaller channel for transmitting to the client as well.

That’s very interesting!
My squeaky Wheel node seems to connect well enough on 40mhz channel that it’s not enough to trigger a step down.
I wonder if I adjusted the AGC for that case if that would be the straw (so to speak) that breaks the 40 down to 20… Hmmm…( have the AGC set to accomodate that link while I do testing. It’s quiet enough around here that it’s not posing a problem, but I’m unhappy with it where it is even though it’s not an apparent issue. It could become one.

I also note that your 20mhz client is also MCS 1… whereas mine shows 5/5 in 40mhz, and 6/7 in 20mhz…

From the Mimosa AP side, I also find it interesting when in 20mhz, the tests they do show 30-50mb, and the system says 144/144 (on average). While in 40mhz, I’m showing 240mb/240mb, and they’re showing essentially double their old with 60-100mb…
So, I think these numbers are in line with going from 20-40mhz channel size.

The thing now is to see if the incoming weather (no precipitation expected, just MUCH colder temps) has a negative impact on the 40mhz channel.

This clip shows 20mhz over 40mhz with no other changes…

This client, unlike the others, is mounted with only an azmiuth change possible. If I can get em to change to a different mount, I think their numbers would be a LOT better. Right now, they have no tilt up, and to me that’s evident when compared to the other links, not only being superior, but visually, you can see this one rather mobile while the others barely move a muscle.

Azimuth is very important, it’s one of the few complaints I have with Mimosa equipment. Radio/Antenna combos like Ubiquiti’s PowerBeam 5AC Gen 2 that have a really nice up/down tilt adjustment which helps a lot with fine alignment especially on long distance links.

Ya, I am not proud of that customer’s link, I think he might be on the docket for getting a realignment from our windstorm a week ago… But that’s not why I posted the picture, it was mostly to prove I wasn’t crazy and that Mimosa Equipment will down shift channel sizes instead of dropping a customer…

We’re in “wireless” crazy is required per training manuals… :slight_smile:

No – it’s good to see what you said so to speak.

…and yes… I wish Mimosa’s “alignment” mechanics were like quite a few other vendors of similar equipment…

Now one of my local ISP vendors is taunting me with a Ubiqiti 2gb PtP that apparently was recently released — I don’t follow that line too close since I don’t really see a lot of changes in their lines… 2gb on 24ghz with a claim of 20km. Hmmm… on 24ghz? However you need deep pockets – I found it was averaging over 3k…per side! Better have a lot of customers or know you can fill the void…

I’d love to move to 24ghz, but thus far Mimosa’s version, based on designer ain’t gonna play. Maybe they have some enhancements coming out. Can’t let the competition sneak in… Mind you I have nothing at all against the big U, just that it’s awfully awfully expensive to do similar tasks…

…there I go again…I digress… Never was good at math, but I sure know how to make a lot of tangents!

Back to the labor of love… Thanks for sharing your results.