Hi people,
I was wondering what kind of sector antennas you use for you ePMP1000/2000 APs.
Until now we used Cambium ePMP 90 Degrees Sector, Ubnt 90 Degree 17dBi Sector and MTI 60 Degree Sector for high interference sites.
What is your experiece with 3rd party sector antennas?
vmiskos, I'd recommend the Cambium sector antenna! We design our own antennas and have an antenna design center of excellence as we trust in our expertise to create antennas that are superior to competing options that fit our devices hand in glove. Our sector antennas have 18dBi gain (1dB higher than the UBNT 5GHz17-90), wideband frequency response from 4.9 to 6.0 GHz with consistent gain, better null fill, and a high front to back (F/B) ratio.
Null full is important when your AP and antenna are installed high on a tower and you have customers close to the AP location. This is because antennas with narrow elevation patterns could be receiving Subscriber Module (SM) signals into a null, resulting in poor to no connection. With null fill the elevation pattern is broader and nulls between side lobes are filled in resulting in much better connectivity to SM's close to the AP.
Our F/B ratio is 35dB. With a high F/B ratio frequency reuse is facilitated with greater results than antennas with poor F/B ratios. I couldn't find the F/B specs of the other antennas. UBNT does not publish this in their antenna data sheets, but I'm confident that our 35dB is superior. With frequency reuse the F/B comes into play because it dictates the imposed secondary self-interference. Consider two AP's on a tower - one facing North and another facing South. Because they are 180 dgrees apart and we support sync you can reuse the same channel. With sync both AP's will transmit and receive at the same time. SM's to the north of that location transmitting to the tower will have their signals arrive at the same RSL to both the North and South AP because the AP's are at the same location, but the South facing AP will receive the signal 35dB lower because of the F/B ratio since the signals are being received behind it. These signals are essentially noise for the desired signals of SM's to the south of the tower transmitting to that AP at the same time as the SM's to the north. The higher the SNR the higher the modulation mode and the F/B ratio dictates the SNR so it's important to have a high F/B ratio. The above explains UL secondary self-interference and the same is true for DL secondary self-interference.
For your high interference areas you should also consider the beam steering antenna aka smart antenna that steers a tighter UL beam towards communicating SM's instead of listening to 90 degrees of RF, which would include the desired signal as well as noise from interfering sources.
Hope that helps!
We had a lot of Ubiquiti in the air when we started moving over to ePMP so in the beginning we just removed the rocket radios from the Ubi antennas (omni's and sectors) and used the adapters to pop in ePMP 1000's. I don't have the specs in front of me ATM but I think the Cambium sectors have better front/back ratio. We still have a bunch of ubiquit sectors with ePMP 1000's on them but whenever we have to replace a ePMP 1000 we just pull it and the Ubiquiti sector and replace it with a ePMP 2000 and Cambium sector.
We still buy/use the ubiquiti rocket dish with ePMP.
ITElite - Literally the worst antenna I have ever used. The sectors make better omni's than sectors.
KPP antennas are good quality and they make all kinds of combination sectors (also now have 900Mhz MiMo Omni !) but you need to really pay attention to the side lobes / spacing requirements (at least on the ones we have bought in the past). My biggest gripe with the KPP sectors is the bizarre decision to put teeth on the upper bracket tilt adjustment so you can't just loosen the bolt, adjust, tighten the bolts. With KPP (the 2.4/5Ghz combo sectors we have) you have to remove the bolts and insert them into the next notch. You end up having to scavenge those bolts off other KPP antennas when the tower guy inevitably drops one from 100+ feet and you can't find it. The KPP antennas are really well made and as a result they seem to be a lot heavier than any other antenna we use.
RF-Elements. The horns are pretty great and allow you to do some things you can't do with sectors (No side lobes is a pretty big deal when you have no vertical or horizontal space on top of a water tower) but they do not have the gain a sector has. RF-Elements sectors are good also, probably a little better than Cambiums depending on which specs are important to you.
Mimosa, haven't used any yet but looking to try their new "wave guide" sectors.
Mostly unless we need a specialty sector antenna (KPP's dual freq sector or a RF-Elements Horn) we just stick to the Cambium sectors because they are pretty good antennas and it's nice to have the same stuff on all the towers, it just makes life easier.
Thank you for your reply. We know all the specs of the Cambium sectors and how good they are. Just looking for other people's experience.
Thank you for your reply. We did exactly the same with ubiquiti sectors and even up to today some of them are still out there.
Another one that we tried was the Mikrotik sector but had terrible performance and replaced it soon after.
I have not used UBNTs new AC sectors, but if you look at the return loss graph, the beam graphs and the FTB numbers (from the M series days anyway) you'll see a drastic difference between them. the UBNT sectors shift as much as 12 dB on the return loss (bad) the FTB was low to mid-20s for some of the band and the polarities are pretty different on gain and return loss at different points along the way which can impact CPE performance. smooth even graphs with a high front to back and sharp edges are generally more desirable. of course, there are situations that different, but overall, as a sector, smooth and clear for the win.
the only 3rd party antennas I trust over cambiums are the KP performance and Alphas. not all the time though. cambiums antennas have a little wider vertical beam which is great for our area. major changes in elevations.
In most cases, you're probably best off with the Cambium sectors.
As far as third party sectors go, I like RF Elements Carrier Class, which are very similar to the oringinal ePMP 1000 5ghz sector (only the carrier class though - their older 120 and 90 degree sectors were trash). The RF Elements horns also work well, but you typically only want to use those in certain situations... they really aren't a direct replacement for a traditional 90/120 degree sector (you're either giving up a lot of signal, or you're using narrow beams - that can be a good thing in some situations, but not most of the time).
KPP also makes good antennas, and they have some options like dual band antennas that can save money on tower rent in some cases.
I haven't used any of the newer Ubiquiti sectors, so I can't comment on those, but their old sectors were complete trash, with terribly front-to-back ratios... which is why adding third party sheilding to antenna is so popular among ubiquiti users...