Band Pass Filter (BPF)

A BPF is one in which the frequency extending form ωL (or ω1) to ωu (ω2) are passed while signals at all other frequencies are stopped.

fig; Band Pass Filter

\[
|H(\omega)| = 
\begin{cases} 
1 & \text{for } B_1 < \omega < B_2 \\[6pt]
0 & \text{otherwise}
\end{cases}
\]

fig: Gain and Attenuation Relation

Where, w1​ : Lower cutoff frequency and  w2 ​ : Upper cutoff frequency