m Derived High Pass Filter

m Derived High Pass Filter:

The m Derived High Pass Filter T and π sections are as shown in the Fig. 9.32 (a) and (b).

m Derived High Pass Filter

Consider that the shunt arm of the T section resonates at a frequency of infinite attenuation i.e. f which is selected just below cut-off frequency fc. The frequency of resonance is given by,

But for high pass filter, cut-off frequency is given by

Substituting value of fc in the equation for f,

m Derived High Pass Filter

Simplifying equation (1) further,

Variations of Characteristic Impedance (Z0), Attenuation Constant (α) and Phase Shift (β) with Frequency:

The variations of characteristic impedance (Z0), attenuation constant (α) and phase shift (β) with frequency are as shown in the Fig. 9.33 (a), (b) and (c) respectively.

m Derived High Pass Filter

As the characteristic impedance for both the sections i.e. prototype section and m Derived High Pass Filter section, the variation of Z0 in m-derived section is similar to that in the prototype filter section.

The attenuation constant α in the attenuation band is given by,

m Derived High Pass Filter

The phase shift β in the pass band is given by

m Derived High Pass Filter

Updated: November 13, 2019 — 9:38 pm