Parameters
Presets
Antenna Type
Frequency f
2400 MHz
1 MHz to 100 GHz (logarithmic scale)
Antenna Length L
62.5 mm
Ratio to resonant length: 1.00 (1.0 = resonant)
Characteristic Impedance Z₀
50 Ω
Observation Distance r
10 m
—
Resonant Length [mm]
—
R_rad [Ω]
—
Gain [dBi]
—
Beamwidth 3dB [°]
—
FSPL [dB]
Gain vs Frequency
VSWR vs Frequency
Theory
Half-wave dipole resonant length:
$$L = \frac{\lambda}{2} = \frac{c}{2f}$$Radiation resistance & gain: $R_{rad} \approx 73\,\Omega$, $G \approx 2.15\,\mathrm{dBi}$
Free-space path loss:
$$\mathrm{FSPL} = 20\log_{10}\!\left(\frac{4\pi r}{\lambda}\right)\,[\mathrm{dB}]$$VSWR: $\Gamma = \dfrac{Z_A - Z_0}{Z_A + Z_0}$, $\mathrm{VSWR} = \dfrac{1+|\Gamma|}{1-|\Gamma|}$
Applications: RF device certification (EIRP/ERP) · antenna array pre-design · EMC test antenna placement · satellite link budget analysis.