MARITIME – ELECTRICAL & ELECTRONIC CALCULATOR
Radar Range Horizon
A precise tool.
What is the Radar Range Horizon & How does it work?
Radar systems rely on line‑of‑sight propagation, meaning the transmitted radio waves travel in a straight line until they intersect the Earth’s curvature.
The maximum distance at which a target can be detected, known as the radar horizon, depends primarily on the height of the antenna above sea level.
By assuming a spherical Earth with radius ≈ 6371 km, the geometric relationship yields a simple approximation that maritime operators use for quick planning.
d = 1.06 \sqrt{h}
d = radar horizon distance (nautical miles)
h = antenna height above sea level (meters)
h = antenna height above sea level (meters)
Parameters
Result
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Frequently Asked Questions
How do I calculate the radar horizon distance?
Use the formula d = 1.06 * sqrt(h), where d is the radar horizon distance in nautical miles and h is the antenna height in feet.
What factors affect the radar horizon distance?
The primary factor affecting the radar horizon distance is the height of the antenna above sea level. Other factors include atmospheric conditions and curvature of the Earth.
Why is the Earth's radius approximately 6371 km?
This value represents the average radius of the Earth, which is used in calculations to approximate the radar horizon distance.
Can I use this formula for non-maritime applications?
Yes, the formula can be adapted for other applications where line-of-sight propagation is a factor, but adjustments may be needed based on specific conditions.
What units should I use for antenna height and radar horizon distance?
For this calculation, use feet for antenna height and nautical miles for the radar horizon distance.
Results are for informational purposes only and do not constitute professional advice.