Leeson's Oscillator Noise Model
Estimate single sideband oscillator noise characteristics.
L_{n }(dBc)
Δf(Hz)
Click or touch the plot above to read the values
Δf = | - frequency distance from the oscillator frequency | |
---|---|---|
L_{n }= | - single-sideband phase noise spectrum | |
Q_{L}= | - Q-factor of the resonator |
Enter oscillation frequency to find Q-factor of the resonator, you can use SI suffixes in your numbers e.g. 10k would be 10 kilo. Capitalization matters, as 1m would be 1 milli and 1M would be 1 mega.
Description:
Calculations are based on the Leeson oscillator noise model, which gets two asymptotic appearances dependent on whether f_{a} is smaller or larger than half the 3dB bandwidth BW_{3dB} of the resonance circuit in the oscillator.
L_{n }(Δf)=F_{eff }k T / 2Po {1+f_{a}/Δf} {1+(BW_{3dB}/2Δf)^{2}} [Hz^{-1}],
where
F_{eff } - effective noise figure that describes the amplifier under large signal sinusoidal excitation.
Po - output power of the oscillator.
T_{0} = 290 K, k ≈ 1.38×10^{−23} J/K.