RFE 6ghz Horn+4600L not good or bad AP?

So far I have only deployed 4600 APs with the Cambium 4x4 sector and it has been great with expected signals in most cases.

I have a small tower with limited space and low client count, so I am trying out a 4600L with an RFE WB 90deg horn and limiting client distance to around 2 miles. So far Uplink signal has been horrible compared to Downlink signal.

Based on product sheets for the RFE horn at my chosen frequency of 6345mhz it should have a gain of around 15-16db with a -6db azimuth of around 95deg and -3db azimuth of between 55-73deg.

First customer I connected is at .35 miles with clear LOS. Customer is around 25deg from antenna center. Expected DL signal is between 42 (mainbeam) 45 (3db) or 48 (6db) and expected UL signal should be around 52 (main beam), 55 (3db) or 58 (6db).

However, I get 49db DL and 61db UL. So I get weaker than the -6db cutoff estimated signal.

As this was the first client and I got DS11 on both DL and UL, I thought maybe it was a fluke until I just hooked another test client up today. This client was further at 2.1 miles.

Customer #2 I connected is at 2.1 miles. Customer is around 29deg from antenna center. Expected DL signal is between 59 (mainbeam) 62 (3db) or 65(6db) and expected UL signal should be around 69(main beam), 72 (3db) or 75 (6db).

However, I get 65db DL and 79db UL. So I get a little worse than the -6db cutoff estimated signal when I expected somewhere between the main and -3db signal.

Does this mean I do not have the AP antenna azimuth set correctly? It would seem based on specs that I could be around 10-15deg off where I should be and I am usually pretty good at getting AP azimuths set correctly.

Could the RFE horn have a narrower beamwidth than the specs say it should, or could I have a bad AP? I am going to go out tomorrow and double check azimuth, but if it is correct what should I do?

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Here is a map view showing where the SMs fall in relation to the AP assuming I have the AP azimuth set correctly to 225deg.

Here is a photo if I set the map to have the antenna beam be 60deg, which is around the -3db cutoff point on the RFE 90deg horn.

We’ve experienced the same issues with the 4600L + RFE’s 90deg WB horn, and not just that horn either… not sure what’s wrong but we’ve stopped deploying more. We have not seen these issues with the OEM 4x4 sector, or LINQ’s sector antennas for 6GHz.

Here’s an example of a 4600L + RFE 16dBi 90deg asym WB horn antenna. AP TX power is set to 20dBm + 16dBi antenna = 36dBm EIRP. Channel width is 40MHz.

I improved things around 2-3db by adjusting my azimuth. I was around 10deg off from my target.

Anyway I think the big issue with the WB horn is the H/V are not even gains on the -3db cut off when compared to the 5ghz 90deg horns. Also the gain changes depending on what channel you use and the beamwidth also changes depending on the channel.

The older 5ghz horn is a steady 90H/90V at -6db and 60H/60V at -6db. The WB horn is 90H/90V at -6db but 55H/73V at -3db. Also the beam width at -6db is under 90deg when on 4.9-5.9ghz and then over 90deg when at 6.2-6.9ghz.

I would much prefer just a 6ghz horn instead of a one size fits all 5-6ghz horn. Especially because 6ghz is so hampered in the UL direction due to strict power limits unlike 5ghz where the SM can have more EIRP than the AP to make up the difference between SM and AP antenna gain.

I have looked at the LinQ antennas but for just a 2x2 6ghz 90deg AP the size is quite large and for this tower I was looking to save around 50% in costs due to client count by using the 4600L and 2x2 horn. Also, I need the horn as I do not have the space for large antennas. Right now this tower has UI PrismStations horns.

Good info. We decided on the LinQ panel over the RFE from the reviews. Glad we went that route.