Usually defined as two band-pass filter 3 dB at the midpoint between the general points with two 3 Db of the arithmetic mean to express.
Devices that a value of power loss, IL = 10Log (Pl / Pin), independent of frequency, in which Pl is the load power, Pin for input from the power generator.
Relative (insertion) loss provisions equal to or less than the frequency value of the interval between points. BW3 is also called the 3dB bandwidth, the reference point refers to the 3 dB under the frequency interval.
Passband Amplitude ripple;
In a given pass-band frequency band (rate) of the (insert) the greatest change in the value of loss characteristics.
Group delay ripple ;
Group Delay is defined as phase shift changes with frequency derivative, can be simply understood as the phase distortion
Group Delay fluctuation band in a given group delay difference between the maximum and minimum values.
Relative attenuation ;
A given frequency the insertion loss and frequency reference to the difference between the insertion loss .
Stop band ;
Relative loss equal to or greater than a specified value of the band.
That the efficiency of filters, as a ratio in size between 1 to infinity, that is the size of the energy reflection. 1 that all the energy is no wear and tear through. All values greater than 1 indicated that some energy is reflected, that is wasted.