Just wondering if anyone has tried to use a Mimosa N5-45x4 with an ePMP3000?
Based on the specs should this work?
The specs suggest it can be used with 2 2x2 APs but only refer to using the A5C with 4x4.
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I have one mocked up in my office, but haven’t yet deployed it. Should work fine, but you may see signals a few db lower than expected due to the sector being slant polarized and the SM being H/V.
MU may not work ? 3000 can’t use that sector’s beam forming… I guess if you wanted beam forming you could still mount the little beam forming panel for the 3000 separately ?
I wonder if Cambium’s beam forming requiring an entirely separate antenna makes it a lot better than competition’s built in beam forming or what the deal with that is.
3000’s antenna connectors are labeled 0, 1, 2, 3 instead of 1H,2 V , 3H, 4V on the Mimosa antennas and Cambium hasn’t been real open about what is H and what is V on the 3000 so connecting it may be pretty straight forward or you might have to experiment.
Even though the Mimosa is slant 45 the ePMP 1000 2.4Ghz sectors are slant 45 while all the ePMP CPE’s are not and… it’s been 5 years or so but I’m pretty sure back when they first came out and everyone was confused about why they did that they said it doesn’t make any difference (defies logic but pretty sure that’s what they claimed). No idea if that applies to 5Ghz AC or not.
22dBi and 43dB F/B is pretty sweet , would love to know how it works out.
I don’t believe the MU functionality relies on beamforming so I am expecting MU to work just fine.
Would you be able to use an ABAB channel plan with these antennas or is there not enough separation? And if you can, how would you deal with the Front/Back settings for reuse?
If you have to use an ABCD plan it would make it very difficult to find enough spectrum for these antennas to be useful.
MU-MIMO should work fine, Cambium has indicated that less than 45* beamwidth makes things hard, but I imagine 45* would work ok, even if not ideal.
These antennae have a very high FTB ratio so frequency reuse should be fine. That said, at 45* you are looking at ABCD probably. If the sidelobe suppression is as good as mimosa says it is, you might be able to get away with tighter frequency reuse like we often do with RF Elements horns
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Hi… I think you are confusing and using ‘beam forming’ in different contexts.
There is 4x4 sector antenna (which this is) and that can benefit from 3db gains from a Force300 client. If I read the data sheet properly on the Mimosa 4x4 antenna, I would think that it should be able to have 3db RX gains, but not necessarily do any MU-MIMO.
Separately from all that, Cambium also has their Beam Steering Antenna for Upload Beam Steering - and that is separate from MU-MUMO or 4x4 gains, and I would fully expect if we want Beam Steering upload, we would still need to use Cambium’s BSA Panel.
(Edited Jan 10/2021)
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Yep, I actually did not realize that beam forming and beam steering are not exactly the same thing. So I learned something today !
I’m not doubting 4x4 MIMO will work and all the gains that go with it but I guess there is something else I don’t understand regarding MU. There have been several times that others have ask about using other 4x4 antennas with 3000 and the answer has pretty much been that they will probably work but MU may not. When I contacted KPP about using one of their 120° 4x4 sectors with the 3000 they said none of their 4x4 sectors would work for MU and the 3000 and the only thing they had that would was their Omni which was specifically built to do MU with the 3000.
There had also been questions about using the Mimosa 4x4 Omni with 3000 and Cambium thought it would probably work but MU may or may not work with it.
There is the 4x4 antenna (which this is) and that can benefit from 3db gains from a Force300 client. If I read the data sheet properly on the Mimosa 4x4 antenna, I would think that it should be able to MU-MIMO and have the same 3db gains with a 3000 MU-MIMO AP.
Cambium has said that if you use two 90° RF elements horns they would need to be pointed 90° off each other (no overlap) in order for MU to work and they make no mention of any other adverse effect for AC CPE’s. Since no CPE would see both 2x2 horns at the same time, and thus allow MU to work, how would that affect the 4x4 gains you refer to since there really isn’t any 4x4 from the CPE’s view. ?
So I was under the impression that a 4x4 antenna had to be specifically designed for MU… is this not the case ?
Short answer is: YES. The AP needs to have information about the antennas characteristics, and the antenna would have to be built to be suitable for the 3000. So the 3000’s MU-MIMO was designed and programmed knowing that the Cambium 4x4 antenna would be used. Therefor, when the SM’s see each element of the AP’s signal, they know where they are, how separated on the azimuth they are, etc, etc – and the AP can then ‘group’ SM’s based on this info.
Now - if you just throw any old 4x4 antenna up there, the AP won’t really know the info it need to know to be able to do it’s magic.
HOWEVER - Cambium did a good thing and did work on some alternative antennas, and does have the Omni/Split-Sector option in the Radio Configuration now. So - that’ll now work with some additional antennas, and some guy are having good results with two 2x2 antennas pointed at the right spread.
So - YES - you are correct, the 4x4 antenna does need to be specifically designed for MU, and also the AP needs to be specifically programmed for and needs to know the antenna characteristics. So - NO - you can’t throw any old antenna on there and expect it to work. But that being said,… using SplitSector mode, you may (or may not) have good results with other makes/models of antennas now. For me, I’d buy Cambium’s sector - it does a good job, and is supported in their MU-MIMO algorithm.
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For example, I had an N5-360 Omni from Mimosa, and I’ve tried that on a 3000 for MU-MIMO and it has given ‘some’ MU-MIMO results. I’ve never really tested it too fully, because:
- The Cambium 4x4 sector is really incredible, and
- Cambium and KP have worked together on their Omni, so that’s what we use if I needed a 4x4 Omni anyway.
But regardless, I wouldn’t go out of my way to buy any more of an off-brand antenna – I’d rather buy the supported KP solution, or stick with the Cambium 4x4 sector, where we’ve seen times with nearly 100% MU-MIMO
Basically the N5-45x4 antenna comprises of two N5-45x2 mounted on top of each other. It fits two concurrent 2x2 MIMO radios operating on separate channels.
Unfortunately such antenna design contradicts with e3k requirements for both SU Transmit beamforming and MU-MIMO modes. So it is a bad idea to use it with e3k permanently.
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Another example of similar antenna design is RF-E Twin Horn Bracket.
Although it is claimed as e3k compatible it was never approved by Cambium.
It is not recommended to use with e3k either.
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Thank you Boris for the information.
Has Cambium tested and rejected these antennas or are you just saying these are not approved and likely won’t perform well?
Does Cambium offer a list of approved antennas for the ePMP3000?
Generally speaking Cambium tries to make products advantageous against competitors. For e3k such feature as MU-MIMO is our differentiator vs. Mimosa.
MU-MIMO brings specific requirements to antennas limiting compatibility with third-party 4x4 antennas. However we support a verity of e3k antenna options optimized for MU-MIMO.
Another goal is to simplify support efforts reducing it only to officially supported antennas. Typically we say that customer can use any 4x4 antenna with e3k. But MU-MIMO performance is guaranteed only for officially supported and tested antennas. In other words, don’t expect us to resolve issues caused by unsupported antennas.
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That makes sense and I can appreciate the approach to streamline support.
So where can I see the list of approved antennas so I can choose a supported antenna that meets our environmental requirements?
Please find below a table illustrating e3k antenna options.
The Panel antenna is deigned by Cambium.
The Dual-Horn antenna is designed by Cambium in partnership with RF-E.
Omni antennas are designed by KPPA and Itelite per Cambium requirements.
Additionally for the Split Sector e3k supports any antennas like RF-E horns covering non-overlapped sectors.
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