PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

648 Practical MATLAB® Applications for Engineers

title(‘Order=8’)

ylabel(‘Magnitude(H)’);

xlabel(‘W in rad’)

subplot(2,2,4)

plot(f,mag,’o’,omega,abs(h10))

title(‘Order=10’)

ylabel(‘Magnitude(H)’);

xlabel(‘W in rad’)

figure(2)

subplot(2,2,1)

plot(omega,angle(h4)),

title(‘Order=4’);ylabel(‘A ngle’)

subplot(2,2,2)

plot(omega,angle(h6));

title(‘Order=6’);ylabel(‘A ngle’)

subplot(2,2,3)

plot(omega,angle(h8))

title(‘Order=8’);

xlabel(‘W in rad’);ylabel(‘Angle’)

subplot(2,2,4)

plot(omega,angle(h10));

title(‘Order=10’)

xlabel(‘W in rad’);ylabel(‘Angle’)

Back in the command window, the script fi le IIR-yul is executed and the results are

shown as follows (Figures 6.73 and 6.74):

>> IIR-yul

FIGURE 6.73
Magnitude plots of IIR normalized LP digital fi lter of order: 4, 6, 8, and 10 using the function yulewalk of
Example 6.18.

0

1.5

0.5

Magnitude (H)

1

0

0.5 1

Order
 4

0

1.5

0.5

Magnitude (H)

1

0

0.5 1

Order
 6

0

1.5

0.5

Magnitude (H)

1

0

0.5 1

Order
 8

W in rad W in rad

0

1.5

0.5

Magnitude (H)

1

0

0.5 1

Order
 10