The Antenna Downtilt Coverage Radius conversion calculator determines the inner and outer coverage radii of an antenna’s signal area using antenna height, downtilt angle, and vertical beamwidth. It helps engineers design and optimize cell coverage by estimating how far a signal reaches on the ground for given antenna parameters.
Formulas
Inner Radius = H / ( tan(A + BW/2) * 5280 )
Outer Radius = H / ( tan(A – BW/2) * 5280 )
Formula Explanation
- H is the height of the antenna in feet.
- A is the electrical downtilt angle in degrees.
- BW is the vertical beamwidth of the antenna in degrees.
- The tangent function converts angular tilt into a horizontal distance on the ground.
- The constant 5280 converts feet to miles. Results can also be expressed in kilometers or meters if needed.
Uses of this calculator
- Estimating ground coverage radius for cellular base stations.
- Planning antenna installations for uniform coverage and minimal overlap.
- Analyzing how tilt and beamwidth adjustments affect signal footprint.
- Optimizing wireless coverage and reducing interference in network design.
What is the coverage radius for a 150 ft antenna with 5° downtilt and 10° beamwidth?
Input: H = 150 ft, A = 5°, BW = 10°
Output:
- Inner Radius = 150 / ( tan(5 + 10/2) * 5280 ) = 150 / ( tan(10) * 5280 ) = 150 / (0.1763 * 5280) = 150 / 930.86 = 0.161 miles
- Outer Radius = 150 / ( tan(5 – 10/2) * 5280 ) = 150 / ( tan(0) * 5280 ) → tends toward infinity, meaning the outer edge extends far away at near-horizontal angles
- Inner Coverage Radius = 0.161 miles (0.26 km)