RF Elements Sym Horn Sector with ePMP 2000 Smart Antenna

Hi all,

Can the RF Elements Symmetrical Horn Sector work with the ePMP 2000 Smart Antenna? To me this really shouldnt' be an issue, as the Cambium ePMP sector operates independantly to the the Smart beam forming antenna... Although it is probably better suited to a 90 degree sector?

Thoughts? Has anyone tried it already?

Thanks,

Tim

It might work but I doubt you would see the benefits of the smart antenna. assuming you are wanting to use one of the narrow-beamwidth horns (30 or 40*).  The smart antenna forms similarly narrow beams throughout the 90* pattern of the standard sector in order to improve uplink SNR in those beams.  Using the narrow horn you have already done the same.

The 30* horns do work well though.  I have a few 30* units paired with ePMP 1000 access points and uplink tends to be solid MCS 14~15 with CPEs 5~6 miles out and very stable.  

The two solutions really have different use cases.  Covering 360* with narrow horns isn't very realistic because of spectrum constraints, a cluster of wider coverage sectors is a better approach for that.  The horns are ideal when you need higher subscriber density in a sector, have limited horizontal coverage needs, or have a large elevation difference between subscribers and the access point.

Hi Jacob,

Thanks for your thoughts.

Wide horizontal coverage is a nice to have, however the increased vertical coverage makes a lot of sense when considering the expence of expanding vertically. We have a site very high up with clients at distance and clients immediately below...

Technically I think that if we stick to a 90 degree horn, the smart antennae should operate normally. Anyone from Cambium disagree with the summation?

Equally, smaller beam widths would also work, but there would be some overlap. Assuming...

Cheers,

Tim

Hello,

We have not tested ePMP2000 Smart Antenna option with third party antennas. Having said that, functionally, there is no dependency between the Cambium Sector Antenna and the Smart Antenna. The Beamforming/Antenna Selection algorithm running in the ePMP2000 AP uses Rx signal levels and UL packet statistics to determine which antenna performs better for each SM and it is not tied up to any specific sector antenna.

Of course, the characteristics of the sector antenna you select (radiation pattern, gain) will impact the parameters used by the algorithm, and hence the antenna selection for UL, but it should not prevent the ePMP2000 and Smart Antenna from working with your third party antenna.

Regards

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Great, thanks for the feedback Luis. Will let you know when we get around to testing it.

Regards,

Tim

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Hello to all!  My first post on the Cambium Forums.  I have 4ea. of the Cambium 90 Sectors with the Smart Antenna's and the EPMP 2000 Radios deployed on a 100 foot tower.  We are VERY impressed with the performance of the network.  We are doing front to back settings on our Radios using 2 channels at 40MGZ. We accually have the sectors about 70 degrees separated becasue of a mountain on one side of our tower.  No problem with front to back.  We have them also set to 75/25 and 2.5MS with excellent results.  Took a bit of tweaking to come to those settings.  At 75/25 and 20MGZ our phone service that is running on top had bad issues with dropped packets since phone does not retransmit.   I am pushing as much as 140-150Meg ag. to some of my customers.  We use RFE TP-380 antennas with 1000 SM's and also force 200's.  Both perform great.  For tough to reach customers we use RD-30 and 1000 SM's.  VERY pleased with this setup.  NOW as to why I am posting on this string:  I am going to mount 2ea. 60 degree RFE horns (Carrier Grade) with 2ea. Smart Antenna's, with 2ea. EPMP2000's on one mount 60 degrees apart.  We love the new 3.3 release and have all of our radios now set to "Forced Smart Antenna".  I am wondering if anyone has used the RFE Horns (In real world) with the smart antennas?  I figure it will be about 1-2 weeks before I deploy our first set.  I will let everyone know what my results are.  My thoughts on this array is:  I want to "off load" most of my close, 1-3 mile, customers on these Horns.  I will have them about 50-60 feet up on the tower tilted strong down into the subdivisions and the business areas of town.  Hoping to put about half our cusotmers on these Sectors to free up the Big Boy Sectors to handle the 6-10 mile customers.  Also hoping to run these on DFS Channels.  We have one of our MP Sectors that takes several of our Mini Cell Back Hauls running on DFS with no issues.  Thanks to everyone for letting me "Rant"!  Looking forward to you all's feedback!

Thanks!  

Randall

HBE Internet

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@iamrbf wrote:

Hello to all!  My first post on the Cambium Forums.  I have 4ea. of the Cambium 90 Sectors with the Smart Antenna's and the EPMP 2000 Radios deployed on a 100 foot tower.  We are VERY impressed with the performance of the network.  We are doing front to back settings on our Radios using 2 channels at 40MGZ. We accually have the sectors about 70 degrees separated becasue of a mountain on one side of our tower.  No problem with front to back.  We have them also set to 75/25 and 2.5MS with excellent results.  Took a bit of tweaking to come to those settings.  At 75/25 and 20MGZ our phone service that is running on top had bad issues with dropped packets since phone does not retransmit.   I am pushing as much as 140-150Meg ag. to some of my customers.  We use RFE TP-380 antennas with 1000 SM's and also force 200's.  Both perform great.  For tough to reach customers we use RD-30 and 1000 SM's.  VERY pleased with this setup.  NOW as to why I am posting on this string:  I am going to mount 2ea. 60 degree RFE horns (Carrier Grade) with 2ea. Smart Antenna's, with 2ea. EPMP2000's on one mount 60 degrees apart.  We love the new 3.3 release and have all of our radios now set to "Forced Smart Antenna".  I am wondering if anyone has used the RFE Horns (In real world) with the smart antennas?  I figure it will be about 1-2 weeks before I deploy our first set.  I will let everyone know what my results are.  My thoughts on this array is:  I want to "off load" most of my close, 1-3 mile, customers on these Horns.  I will have them about 50-60 feet up on the tower tilted strong down into the subdivisions and the business areas of town.  Hoping to put about half our cusotmers on these Sectors to free up the Big Boy Sectors to handle the 6-10 mile customers.  Also hoping to run these on DFS Channels.  We have one of our MP Sectors that takes several of our Mini Cell Back Hauls running on DFS with no issues.  Thanks to everyone for letting me "Rant"!  Looking forward to you all's feedback!

Thanks!  

Randall

HBE Internet


firstly, welcome to cambium forums!!! 

the horns are a different animal, but they do work well. 

few big things to note,   the sectors you have match the width and similar gain  to the smart antennas, the horns do not.   it will work to mix them, but be aware of your antenna patterns when depending on two different antennas for operation to a single client.   

the horns produce a circular pattern, so if you tilt the horn enough your signal isn't on the horizon, you will need to apply the loss in your beamwidth to match your tilt.   if you leave them flat, in close and near expected edge of the horn, you may end up in a dead spot again because of its round shape.        you very likely at some point will see a CPE with a poor downlink, but great uplink as well as possibly reversed because of the shape difference in the beam partterns of the two antennas. 

the wider the angel of the horn, the less gain it has, this is especially important in the DFS area,   you have 2 different restrictions to watch, conducted power and ERIP.      if you pick the wider horns, you won't be able to reach your ERIP limit, reducing your overall system reach.  

the horns excel at cleaning out of sector beam width noise.    as does the smart antenna.    but you've got a catch 22.   the horn likely has a better FTB than the smart antenna.  so if you've got noise on the back side of your tower aggravating it, the horn may be your better uplink choice, and the flipside if your noise is in beam width of your horn, the smart antenna will likely be the better choice.  

the horns have gotten extremely popular with the unsyncable radio systems like ubnt because the radios themselves can't stop from interfering with each other (GPS) and they've somewhat improved that with the prisim stuff, but not exactly a lot.  this isn't a problem cambium suffers from because they've done what no other 802.11 company has... still.     made GPS work correctly. 

in my opinion for what you are wanting to do, either use the 30 degree horns, and use 2 to cover your 60 degree area, or add just one more sector antenna and smart antenna.  

your idea will work, but you'll likely fall a little short of what you are allowed to use ERIP wise witch is why i'm suggesting to stick with the sector, or use two of the tighter horns to maintain your sector gain.     

if you decide to go with that particular combination please let us all know how it goes for you!   I've used a couple 30 degree horns but i have not mixed them with smart antennas.  

Thanks for the reply.

Guess the first part of your reply lost me: "few big things to note,   the sectors you have match the width and similar gain  to the smart antennas"?  According to the Cambium Engineers the Smart Antenna does not have a gain, they are dynamic in nature.  And from my observations on my own setup the 'edges' of the Cambium Sectors seem to be where most of my customer's were that used the sector instead of the smart antenna when the AP was in the 'Auto' position.  Therefore I  believe 60 degrees is the 'strong' area of the smart antenna's performance.

As far as the tilt of the Horn as I stated I am not concerned about the Horizon this setup is for in close customers only.

Most of the other info in your reply, although true, is basic spec sheet info.

Most likely MY Fault for not stating what I would like to know is:  Has anyone used the Smart Antenna with an RF Elements Horn... no matter what the gain of the horn? 

And yes I will post the results using both DFS channels and non DFS channels.

Again.... Thank you for your reply.... time and experience is valueble and I appreciate yours!

Good Day,

Anyone finished any testing of these?

Our problem is we have a tower where we are only allowed a single tower section to put our kit. These RF elements are much smaller than any other available. The general consensus we are hearing is it "should" work (we intend to use the 90 degree version).

- David


@dmcken wrote:

Good Day,

Anyone finished any testing of these?

Our problem is we have a tower where we are only allowed a single tower section to put our kit. These RF elements are much smaller than any other available. The general consensus we are hearing is it "should" work (we intend to use the 90 degree version).

- David


they do work just fine, the disadvantage of these units, the 90 degree particular is low gain, only 10db.     the cambium sector is 17db.      no ability to tilt these down from the horizon, so they are extremely susceptible to on channel horizon noise if you are running sectors only and no steering antenna.   

the horns excel at canceling noise outside of their beamwidth and preventing receive saturation from said problem.

traditional sectors can be tilted to remove horizon noise, higher gain at this particular beam width.   the horns are a great supplements and tool, but IMO are not a suitable replacement for sectors.   particularly horns over 40 or 50 degrees from the gain challenges. 

how much verical space do you have?   we generally get 4 sectors and 2 backhauls in the same verical 3' space on a tower using sector frames from site pros1.com   (the wimax frame) 

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To second Chris, the horns work great but aren't always the right tool for the job.  If you need smaller sectors than the Cambium OEM units look at the Ubiquiti "mid-gain" titanium units. They can be set to 60/90/120* and are quite good.

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Just a quick update here for all looking into this. Any suitable sector antenna may be used with the ePMP2000, however the beamforming antenna cannot be subsituted as its a powered device and no other antenna will work on those ports to provide beamforming capabilities. For instance you CANT use 2 x 30 degree RFE horns to get super sweet coverage :-D.

Cheers.