Access Point AP 277 orientation
10-24-2018 02:10 PM
Our AP installation vendor placed 12 AP model 277s on the exterior walls of a logistics building. The intent is to provide coverage for exterior yard scanning equipment within 120-150' of the exterior wall.
The AP 277s are mounted approximately 27' high (over semi-trailer bay doors), on AP-270-MNT-V1 – 18” Mounting Arms. The APs are physically oriented with the flat surface facing the ground. The AP-270 Installation Notes show photos/diagrams of the AP-277s mounted so that their horizontal plane runs parallel with the wall (at a 90 degree angle). I've attached 2 photos from the Installation Notes for reference.
Will the APs mounted in their current horizontal fashion (flat-side down) result in diminished radiation pattern? If so, I can have them re-orient 90 degrees outward. WIth that question in mind, what signal levels have you observed at the 120, 150 ft marks with the AP 277s? I have them configured for ARM range 18-21.
Re: Access Point AP 277 orientation
10-25-2018 12:25 AM
Depending on the area you need to cover I ususally orient the 5 - 10 degrees down.
There is a difference between mechanical downtilt and the downtilt built into the antenna by design. If you do a google for antenna mechanical downtilt there are a number of diagrams explaining this. I'd also do a search for the antenna graphs of the AP-277 from Aruba to give you an idea of the distribution of the antenna.
Not using mechanical downtilting can result in the most 'intense part' of the signal going over the top of the desired area of coverage (depending on the antenna pattern and use case). However, introducing too much mechanical downtilt can also result in reduced coverage.
Think of a spotlight analogy - if you tilt it too much all you get is a small dot of coverage on the floor, if you tilt it too little the light does not reach the are you are trying to cover as it goes over the top.
I hope that helps
University of Cambridge