How do I calculate bandwidth frequency?

The Q factor of the pMUT can be determined by the real part of the impedance frequency spectrum, which is defined as Q = f r/Δf , where the resonance frequency fr is the frequency at which the real part of the impedance reaches its maximum, Δf is the width of the peak at its half height, so-called 3 dB bandwidth.

The bandwidth of a signal is defined as the difference between the upper and lower frequencies of a signal generated . As seen from the above representation, Bandwidth (B) of the signal is equal to the difference between the higher or upper-frequency (fH) and the lower frequency (fL).

Δf=fH−fL=f2−f1=2πLR .

The bandwidth of any system is the range of frequencies for which the current or output voltage is equal to 70.7% of its value at the resonant frequency , and it is denoted by BW.