A band-pass filter attenuates frequencies below a lower cutoff point and above an upper cutoff point, leaving a specific window of frequencies relatively untouched. This is achieved by combining low-pass and high-pass filter elements. Engineers use them heavily in radio receivers to tune into a specific channel while rejecting adjacent signals and background noise.
We need a narrow band-pass filter on the input to isolate the 455 kilohertz intermediate frequency.
Related terms
Band-stop
Describing a circuit or filter that blocks a specific range of frequencies while allowing all others to pass.
Highpass
Describing a filter that allows high frequencies to pass through while attenuating lower frequencies.
Lowpass
A type of filter that allows low-frequency signals to pass while blocking higher frequencies.
Roll off
To gradually attenuate a signal's amplitude as its frequency moves past a specific cutoff point.