Knowledge Base

How do I find the tower with the strongest cell signal in my area?

A roof-mounted outdoor directional antenna needs to be pointed in the direction of the strongest cell signal. There are three ways to find the best direction to aim your directional antenna. sample map image You can find the location of local cellular towers using Cellmapper. (Click to enlarge.)
  1. Use Cellmapper. Cellmapper is a crowdsourced website that collects data about cellular towers from people who use its smartphone app. Use these direct links to maps for Verizonexternal link icon, AT&Texternal link icon, T-Mobileexternal link icon, UScellularexternal link icon, or GCI Alaskaexternal link icon. Move the map by clicking and dragging; zoom in to your location with the scroll wheel on your mouse or use pinch-to-zoom on touchscreen devices.

    Cell towers appear as large green or red circles; their labels tell you which bands of cellular frequency they’re broadcasting. Point your directional antenna toward the closest tower; try other local towers until your signal booster is giving you the best signal.

    (Android users can use Network Cell Info Liteexternal link icon to check signal strength and Speedtest by Ooklaexternal link icon app to check download speeds. iPhone users may be able to get signal strength in Field Test Mode; to check download speeds, use Speedtest by Ooklaexternal link icon for iOS.)

  1. Do an eight-point antenna test. You can perform this test if you have a cell signal booster with an outside directional antenna. Point the outside directional antenna due north. Wait a couple of minutes, then check your phone’s signal strength or download speed near the booster’s inside dome or panel antenna.

    Next, point your directional antenna northeast, wait a couple of minutes, and do another signal/speed test inside. Repeat this for east, southeast, south, southwest, west, and northwest. Write down the results you get for each direction as you go. Whichever direction gives you the strongest signal or fastest download speed, point the outside antenna in that direction and lock it in there.

Nextivity WAVE smartphone app Settings tab Nextivity WAVE smartphone app (click to learn more)
  1. Use Antenna Position Test in the Nextivity WAVE smartphone app. If you have a CEL-FI cell signal booster and a directional antenna, download the Nextivity WAVE app for Android or iOS and tap Settings > Antenna Settings > Antenna Position Test. (See this screenshot.) The app will walk you through an eight-point antenna position test (described in #2, above) and tell you which direction has the strongest signal.
  2. Do a four-point site survey. If you haven’t yet purchased a cell signal booster, you can still use the same tools in #1, above, to test the signal around your home. Stand outside your home and run four signal strength and/or speed tests, one on each side of the house. The side with the best results is likely to be facing the direction of the strongest tower. Once you’ve purchased a cell signal booster, you can start your eight-point test by pointing your antenna in that direction.