Information about RF Band Reject Filters

RF band reject filters (bandstop filters, notch filters) are tuned circuits that prevent the passage of signals within a specified band of frequencies. Performance specifications for band reject filters include specified frequency, bandwidth, ripple, insertion loss, and voltage standing wave ratio. The specified frequency is the center frequency. Bandwidth is the range of frequencies that RF band reject filters pass with maximum attenuation. Ripple is the peak-to-peak variation of the passband response. Insertion loss is the total RF power transmission loss resulting from the insertion of a device in a transmission line. Insertion loss is the ratio of signal power at the output of the inserted device to the signal power at its input. Voltage standing wave ratio (VSWR) is a unit-less ratio ranging from 1 to infinity that expresses the amount of reflected energy. A value of 1 indicates that all of the energy passes. Any other value indicates that a portion of the energy is deflected. VSWR can also be expressed in terms of decibels (dB).

Products & Services Related to RF Band Reject Filters

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RF high pass filters pass signals from high frequencies and reject signals from low frequencies.

RF Low Pass Filters

RF low pass filters pass signals from low frequencies and reject signals from high frequencies.