Leeson's equation - Alchetron, The Free Social Encyclopedia

Leeson's equation is an empirical expression that describes an oscillator's phase noise spectrum.

Leeson's expression for single-sideband (SSB) phase noise in dBc/Hz (decibels relative to output level per Hertz) and augmented for flicker noise:

L ( f m ) = 10 log ⁡ [ 1 2 ( ( f 0 2 Q l f m ) 2 + 1 ) ( f c f m + 1 ) ( F k T P s ) ]

where f₀ is the output frequency, Q_l is the loaded Q, f_m is the offset from the output frequency (Hz), f_c is the 1/f corner frequency, F is the noise factor of the amplifier, k is Boltzmann's constant in Joules/Kevin, T is absolute temperature in Kelvins, and P_s is the output power.

References

Leeson's equation Wikipedia

(Text) CC BY-SA