5.1.2 Illustration of Effects of Group Delay and Attenuation zeros:z=,98e±j8r,8个2重零点：z=1/c=1/0.95e干j15r+.02x利 >Poles:?=0.8ej,4杯，8个2重极点：z=ck=0.95e+j(.15r+.02x k=1,2,3,4. 1 0.8 H2(z)represents an 0.6 allpass system 0.4 0.2 H2(e/w)川=1 for all w. 0 0.2 H2(z)introduces a large -0.4 0.6 amount of group delay 0.8 over a narrow band of -1 -0.5 0 0.5 frequencies. Real Part Figure 5.2 Pole-zero plot for the filter 23◆zeros: 5.1.2 Illustration of Effects of Group Delay and Attenuation Figure 5.2 Pole-zero plot for the filter H2 (z) represents an allpass system H2 (z) introduces a large amount of group delay over a narrow band of frequencies. 23 ◆Poles: ,8个2重零点: ,8个2重极点: