Q factor

Q factor is a measure of the "quality" of a resonant system. Resonant systems respond to frequencies close to the natural frequency much more strongly than they respond to other frequencies. On a graph of response versus frequency, the bandwidth can be defined as the "full width at half maximum" or FWHM. The Q factor is defined as the resonant frequency divided by the bandwidth:

Q = ω₀ / Δω

In a TRF[?]:

<math>Q = \frac{1}{R} \sqrt{\frac{L}{C}} </math>