Passband
frequencies or wavelengths that can pass through a filter
A passband is the range of frequencies or wavelengths that can pass through a filter. For example, a radio receiver contains a bandpass filter to select the frequency of the desired radio signal out of all the radio waves picked up by its antenna. The passband of a receiver is the range of frequencies it can receive when it is tuned into the desired frequency as in a radio station or television channel.
A bandpass-filtered signal (that is, a signal with energy only in a passband), is known as a bandpass signal, in contrast to a baseband signal. The bandpass filter usually has two band-stop filters.
Filters
In telecommunications, optics, and acoustics, a passband (a band-pass filtered signal) is the portion of the frequency spectrum that is transmitted (with minimum relative loss or maximum relative gain) by some filtering device. In other words, it is a band of frequencies which passes through some filter or a set of filters.
The accompanying figure shows a schematic of a waveform being filtered by a bandpass filter consisting of a highpass and a lowpass filter.
Radio receivers generally include a tunable band-pass filter with a passband that is wide enough to accommodate the bandwidth of the radio signal transmitted by a single station.
Digital transmission
There are two main categories of digital communication transmission methods: baseband and passband.
Begin with the source’s own compact description: “Passband” is frequencies or wavelengths that can pass through a filter. The dossier treats that line as a proposition to test through Passband, frequencies and wavelengths, not as a finished interpretation.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Oct 31, 2025. The linked authority identifier is Q254758. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Passband” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.