AntennaSim — Ham Radio Antenna Analyzer

AntennaSim

N1DKE

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Antenna Type

Select Type

Frequency

Band Presets

Center Frequency (MHz)

Sweep Range (±MHz from center)

Environment

Height above ground (m)

Wire conductor

Help / Reference

SWR (Standing Wave Ratio)

SWR of 1:1 is perfect. Below 2:1 is excellent for most rigs. Above 3:1 may cause transmitter fold-back. Your tuner can handle most mismatches.

Gain (dBd / dBi)

dBd = gain relative to a dipole. dBi = relative to an isotropic radiator. dBi ≈ dBd + 2.15. More gain = more signal in the favored direction.

Radiation Pattern

The 2D polar plot shows signal strength (dB) vs. direction at a fixed elevation. The 3D view shows the full radiation envelope. Bigger lobes = more signal that direction.

Takeoff Angle

The elevation angle of maximum radiation. Lower = better for DX. Higher = better for NVIS/regional comms.

Efficiency

Accounts for conductor and ground losses. 100% = all power radiated. Typical real-world dipoles: 85-99%.

Configure antenna parameters and press SIMULATE

Wire Analysis

Band Performance Summary

Band	Freq (MHz)	Harmonic	Gain (dBi)	Feed R (Ω)	Feed X (Ω)	SWR

SWR Sweep — Per Band