PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

566 Practical MATLAB® Applications for Engineers

R.6.25 The design of any of the fi lters defi ned in R.6.22 is accomplished by fi rst designing
a normalized LPF prototype. A normalized LPF is a fi lter with a cutoff frequency
of wp = 1 rad/s connected to a load of R = 1 Ω.

R.6.26 The normalized LPF will be implemented employing electrical elements using
the notations Rn, Ln, and Cn (referred to as normalized resistors, inductors, and
capacitors).

FIGURE 6.3
LP and HP fi lter’s (magnitude and phase) characteristics.

Pass band Stop band

0 0

0 0

wp

w

|H(jw)|

H(jw)

Stop band Pass band

wp

w

|H(jw)|

(b)

wp

w

H(jw)

(a)

wp w

FIGURE 6.4
BP and BR fi lter’s (magnitude and phase) characteristics.

Stop bandPass bandStop band

0 wl wu

wl wu wl wu

W

|H(jw)|

Pass bandStop band Pass band

0 wl wu W

|H(jw)|

(d)

0

W

H (jw)

(c)

0

W

H(jw)