Mount higher, reduce obstacles, and improve link margin. Enter site data and get recommended height. Use clear outputs to coordinate crews and permits quickly.
| Parameter | Example value | Notes |
|---|---|---|
| Link distance | 5.000 km | Point-to-point path length. |
| Frequency | 2.400 GHz | Typical unlicensed link frequency. |
| Site A elevation | 120.00 m | Ground elevation at Site A. |
| Site B elevation | 135.00 m | Ground elevation at Site B. |
| Site B height | 12.00 m | Mounting height above ground. |
| Obstacle distance | 2.000 km | Measured from Site A. |
| Obstacle elevation | 140.00 m | Ground at obstruction location. |
| Obstacle height | 18.00 m | Tree line or structure height. |
| Fresnel fraction | 0.60 | Clears 60% of r1. |
| Extra margin | 1.00 m | Accounts for installation tolerance. |
Mounting height is a construction decision with measurable link impact. This calculator turns survey inputs into a minimum Site A height that keeps the straight path above critical features. By working in antenna-tip elevation, it aligns rooftop levels, mast lengths, and terrain in one reference frame. Use it during design review to avoid late changes caused by parapets, cranes, or nearby structures. It also helps coordinate rigging, access, and structural checks before procurement begins onsite.
A path can look clear and still underperform due to diffraction. The first Fresnel zone approximates the volume where energy concentrates, and partial blockage increases fading. Selecting a clearance fraction, such as 0.60, adds a realistic buffer. Higher frequencies reduce Fresnel size, while longer spans increase it, so clearance is vital across mixed-rise sites and industrial corridors.
Over distance, Earth curvature raises the apparent profile between sites. The k-factor models atmospheric refraction that bends radio waves; 1.333 is common for planning, but conditions can vary. A positive margin protects against alignment tolerance, seasonal foliage, and temporary obstructions. For long crossings or low-clearance routes, test a slightly lower k to understand worst-case height needs.
Accurate results depend on meaningful obstacle points. Measure distance along the intended azimuth, then record the obstacle ground elevation and its height above ground for trees, roof edges, signage, and mechanical units. Enter up to three governing locations: the highest ridge, the closest blocker, and the tallest structure. The calculator uses the controlling point to set the minimum height.
Construction teams need traceable assumptions. The CSV supports design sheets and cost comparisons, while the PDF is useful for permits, method statements, and QA records. The obstacle table shows required point height versus the line height at each location, helping you explain PASS or FAIL outcomes. Use the recommended practical height for procurement, then confirm as-built measurements before commissioning.
It is the smallest antenna height above Site A ground that clears every obstacle after adding curvature bulge, the chosen Fresnel clearance fraction, and your extra margin.
Partial Fresnel blockage can cause diffraction loss and fading even when the path looks clear. Clearing a fraction, such as 60%, improves stability and reduces outage risk.
Use 1.333 for typical planning. In coastal, desert, or inversion-prone areas, run checks with a lower k to represent weaker refraction and more apparent curvature.
Start with conservative values from maps or range data, then replace them with surveyed elevations. Better obstacle data reduces overbuilding and improves confidence in the selected mast length.
Yes. Enter rooftop levels as site elevations, then treat parapets, adjacent roofs, or mechanical units as obstacles using height above ground at their locations.
PASS means your planned Site A height keeps the line above the required point height at that obstacle. FAIL indicates you need more height, a different mounting spot, or a revised path.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.