Rejection

__ESTIMATING REJECTION PERFORMANCE__

Bandpass Filters - Rejection can be determined at any frequency outside of the 3 dB bandwidth for any design with the following values: Center Frequency (F

To determine the Rejection (dBc) at a Rejection Frequency:

- Normalize your data using the following formula:
- Number of Bandwidths = (Rejection Frequency - F
_{c}) / BW_{3dB} - Select Rejection Plot - Select using the applicable percent BW
_{3dB. } - Note that these rejection plots represent an approximation for the indicated filter topologies at the required bandwidth.
- Determine Rejection (dBc) using the Rejection Plot and Number of Bandwidths
**.**

__REJECTION PLOTS__

__Rejection Plot 5-8% BW___{3dB }(Combline/cavity and ceramic resonator filters )

Rejection Plot 9-12% BW_{3dB }(All topologies)

Rejection Plot 13-16% BW_{3dB} (Lumped element and combline/cavity filters)

Rejection Plot 17-20% BW_{3dB }(Lumped element and combline/cavity filters)

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