BaiTip of the Day - February 24th, 2017 - Every dB Counts!

This week, I toured several operators in the Southeastern US, an area full of tall thick pine trees and rolling terrain. I was very impressed with our Baicells LTE equipment’s ability to penetrate some very nasty foliage. However, I would like to provide some suggestions to help operators deploying in this type of topology, where Every dB Counts!

Deploy narrow sectors (65 degree or less) in dense foliage areas to concentrate more RF energy to your client locations. Every dB Counts!

Install Low PIM 1/2" jumper cables to the sectors. Every dB Counts! Here is a link to an online Coax Attenuation Calculator, http://www.timesmicrowave.com/calculator/?productId=31#form. Additionally, here is an article about Passive Intermodulation (PIM). http://www.commscope.com/Blog/CommScope-Definitions-What-is-PIM/

Use an electronic protractor or inclination phone app to adjust sector down tilt affordably or invest in more expensive equipment to do so. Normally in thick foliage areas, distance will be more limited than open terrain, therefore, sector down tilt can be increased. Every dB Counts!

Calculate the UE antenna tilt angle with an online calculator such as http://www.cleavebooks.co.uk/scol/calrtri.htm. Enter two known values such as tower antenna mounting height and link distance and the calculator will yield the proper tilt angle. Don’t forget to add or subtract elevation changes between the client location and the base of the tower, when entering the vertical side in the online calculator. For example, if the base of the tower is at 850’ and the client location is 700’, with a 200’ mounting height, the proper vertical measurement would be 350’. This information should be given to the installer before leaving for the install. A phone app should be adequate to properly adjust the UE antenna face at the client location. An example image is given below where edge a is tower mounting height plus change in terrain elevation (200’ + 150’ = 350’) and the link distance is 3 miles or 15,840 feet. This installation should have a 1.27 degree up tilt on the UE face. Every dB Counts!

Use Google Earth or other application to draw a line between the tower and the client location. This will assist the installer pointing the antenna in the proper direction, shorten installation time and give the customer better performance. It is usually good to provide an image of the entire path and a close up image, to assist with pointing to landmarks and avoiding known obstacles, such as the big trees in the second image below. In this example, moving the UE 20’ to the back of this house, the installer could have avoided shooting into the tree trunks of some very large trees in close proximity. Since the tower was not visible, the installer could not tell. Impress on your installers, Every dB Counts!

Make sure your installers avoid blocking any portion of the UE antenna face by mounting under eaves or behind pipes or chimneys. Every square inch of the antenna face is valuable real estate to insure Every dB Counts!

Don’t sacrifice performance, Every dB Counts!

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