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Calculators / Dipole Antenna
Dipole Antenna
Calculator
Calculate the optimal length of a half-wave dipole antenna based on frequency, conductor diameter, and velocity factor. Professional RF engineering tool for precise antenna dimensions.
Radiating Element
Coaxial Feed
⚙ Half-Wave Dipole Engine
Affects length via thick-dipole correction
Wave speed ratio conductor vs free space (0.95 = bare copper)
Affects loss resistance & efficiency
Advanced Parameters
End capacitance shortening (0.95–0.98 typical)
°C
Scales conductor resistivity
m
Modifies feedpoint impedance
SWR: —
Calculated Results
Total Length (L)
—m
Arm Length (L/2)—
Wavelength (λ)—
Radiation Resistance—
Loss Resistance (Rloss)—
Radiation Efficiency—
Feedpoint Impedance—
SWR (vs feed line)—
Gain (dBd / dBi)0.0 / 2.15 dBi
Enter values above to calculate.
📖 The Fundamental Theory
A half-wave dipole consists of two identical conductive elements arranged symmetrically. Total length ≈ λ/2 at the operating frequency.
Core Formula
L = (143 × k × e) / f
L in metres, f in MHz, k = velocity factor, e = end-effect. Diameter adds thick-dipole shortening.
Conductor diameter affects length via the thick-dipole shortening factor. Material resistivity determines loss resistance and radiation efficiency.
📡 Radiation Pattern Viewer
Live Simulation
|
Dipole Type
Simulation Ground
Frequency Tuning
144 MHz
Height Above Ground
0.50 λ
E-Plane (2D)
3D Gain Pattern
ℹ
Pattern Analysis Insights
Half-wave dipole free-space pattern: classic figure-8. Max gain ≈ 2.15 dBi broadside, deep nulls along antenna axis.
Common Applications
Amateur Radio
Most popular HF/VHF antenna due to simplicity and performance.
FM Broadcast
Base element for vertical FM transmission arrays in broadcast stations.
RF Experiments
Reference antenna for testing signal strength and gain of arrays.
Education
Standard model for teaching electromagnetics and antenna theory.
Get "10 RF Design Principles Every Engineer Should Know" Free
Learn practical principles for better RF circuits, PCB layouts, simulations, measurements, and troubleshooting.