Omnidirectional AP tower separation

Hello everyone,

I have a Cyclone 5.7 Omni AP on a tower about 150Ft high.
Our AP sits right before the top of the tower on a stand-off bracket about 12 inches apart.
Performance is not as good as expected. Bare SM’s located about a mile away receive an RSSI of 780 with jitter of 1. Link evaluation on 1X shows 100% both directions, 2X is 97%.
Spectrum is quite clean.
Are these normal readings or we can benefit form separating the AP form the tower a little bit more than that?

Thanks,

this is what we see with all of our 5.7 ap omnis, we have tried many different antennas and have come to the sad realization that 6 to 7 miles with a reflector will give us a 400-500 rssi which we have found to be the max safe zone for us, sms without reflectors are very short ranged like you said, for this reason we have begun to bite the bullet and just spend the money for clusters, we have found this to be so much less maitnance and you dont have to worry about connectorizing your aps, just my 2 cents, craig

you can always try stingers. they help alot

Or grids from advanced antenna…A lot will depend if you have los from sm to ap…

But the fact that the AP is side mounted on the tower with 12 inches of separation does not compromise coverage?

Will using a 3Ft side mount improve coverage?

BTW, we do have LOS to the AP in every registered SM.

Thanks!

Found my answer! :smiley:

Just to share with the rest of the forum, I found this on www.michwave.com BTW our antenna cannot support the extra wind drag of a 1 meter standoff mount so we are installing a short pice of pipe at the top of the tower and placing our AP above it to radiate 360 without obstructions.

Ideally, an omni antenna should be placed on the tip of a mast above a tower. This will give a nice circular radiation pattern. If your tower is 300 feet high and you wish to place the omni at the 100 foot level, you will have to attach the omni to a stand-off bracket at some distance away from the tower leg. With a spacing of 6" or even 12", you will have many lobes and nulls created by the reflections from the tower. Also with close spacing, there is a greater chance that these reflections will produce an upwards or downwards beam tilt. The depth of these nulls can be reduced by a greater spacing, such as 5 feet. Make sure that your tower can handle the extra wind load of these stand-off brackets, and that the omni antenna is parallel to the tower legs at all times.

Thanks to all!

Putting the omni at the very TOP of the tower isn’t an idle situation either because now it is the highest most point and most likely to get hit by lightening.

The plan is to still use a side mount with a little elevation just to clear the tip of the tower. We are extending the lightening rod so it will remain the highest point in the tower posing little to none blockage to the omni pattern.