TECHCENTER

A band pass filter (also known as a BPF or pass band filter) is defined as a device that allows frequencies within a specific frequency range and rejects (attenuates) frequencies outside that range.

The low pass filter is used to isolate the signals which have frequencies higher than the cutoff frequency. Similarly, the high pass filter is used to isolate the signals which have frequencies lower than the cutoff frequency.

By the cascade connection of high pass and low pass filter makes another filter, which allows the signal with specific frequency range or band and attenuate the signals which frequencies are outside of this band. This type of filter is known as Band Pass Filter.

The Band Pass Filter has two cutoff frequencies. The first cutoff frequency is from a high pass filter. This will decide the higher frequency limit of a band that is known as the higher cutoff frequency (fc-high). The second cutoff frequency is from the low pass filter. This will decide the lower frequency limit of the band and that is known as lower cutoff frequency (fc-low).