1、1234221()(5-28)1aNcHj211()()22acacHjHj1(0)20lg20lg23()aacHjdBHj5612c()aHj01N=2N=8N=472221()(5-29)1aNcHjC8()aHjcst2111A()aHj1Acst21111N为奇数为奇数N为偶数为偶数92221()(5-30)1aNHjUst()aHjc110111212021(0.2)10 (5-31)0.21aNcHj152021(0.3)10 (5-32)0.31aNcHj通带条件通带条件12011152022120lg1()()101()1020lg15()aaaaHjHjHjHj130.70
2、32/crads12c 222()0.120930.36400.49450.994550.49451.35850.4945aHsssssss141112121120.2871 0.44662.1428 1.1454()1 0.12970.69491 1.06910.36991.85580.6304 1 0.99720.2570zzH zzzzzzzz151120.2tan2 tan0.65022rad sT 2220.3tan2 tan1.01922rad sT 1612021(0.650)10 (5-31)0.6501aNcHj152021(1.109)10 (5-32)1.1091aNcH
3、j0.76622/crad s 12c 通带条件通带条件172220.2025()0.3960.58711.0830.58711.4800.5871aHsssssss111211 6121212()()0.0007378(1)(1 1.26860.705)(1 1.01060.3583)(1 0.90440.2155)zaszH zHszzzzzzz 18191c 1c 20211c 22232420 (5-33)spppj 0pj 2200sjjj 2522200 (5-34)00 2c 1c ()aHjcc0B()aHj210B0261222202 (5-35)c 22101 (5-36)
4、c 012 21 (5-37)cB 021c27220()()pBPLPspHsHs21cB 281111zpcz22210222200221 (5-38)1czzccscz20spp1111zpcz29tan (5-39)2c 2012tantantan (5-39)22221tantan22cc00tan2c 03000cot2c 2202202cEc220cDc21cot (5-40)2cD 21021cos22cos2 (5-41)cos2E312121 (5-42)1zEzsDz3221211()()(5-43)zEzLPs DzH zHs330coscos (5-44)sinD 模
5、拟低通的通带映射为数字带通的通带模拟低通的通带映射为数字带通的通带模拟低通的阻带映射为数字带通的阻带模拟低通的阻带映射为数字带通的阻带000 ,jsjze 3435120.4 ,0.52012tantantan22200.449421cotcot 0.052ccD 1/crad s 36212102cos2coscos0.3167688822E11220.41400 /0.51500 /ssfkHzrad sfkHzrad s cot 0.056.313751515Dsf371110coscos6.98883225sinstststD 2220coscos10.39143462sinststs
6、tD0coscossinstststD3821210.30.2stst21010log120Nstc 16.98883225stst 3921()1.41421361LPHsss2lg(101)1.1816818362lg(6.98883225)N4021211()()zEzLPs DzH zHs2212340.02025069(1)()1 0.56369681.6392940.44967430.6400452zH zzzzz4120220psp0带阻滤波器阻带中心频率带阻滤波器阻带中心频率4221121(1)1()()DzLPsE zzH zHs4344451c 4611()(5-45)zG
7、 Z11()()()(5-46)dLzG ZHZHzG(.)47481*1111()(5-50)1NiiizazG Za z arg()()()(5-47)jjG ejjjeG eG ee()1 (5-48)jG earg()(5-49)jG e 49501111()(5-51)1zazG zaz5111zZ ccjjzeZesin2arctan (5-52)1cosccccaa:111ccjjzee :111ccjjZee 521111()()(5-53)zadLzazHzHz53545556逼近逼近()H z()dHz逼近逼近()jH e()jdHe572200cos()2()(5-55)cos()2MkjkNllkeH elp01()(5-54)1MiiiNkkkb zH za z5859逼近逼近()h n()dh n60001()()(5-56)1MiiniNknkkb zH zh n za z120()()()(5-57)Pdnh nh nw n1000()(5-58)PNMnikiknikh n za zb z6100(),0 (5-59)()0,(5-60)niniNjja h nibnMa h njMnMN逼近逼近()h n()dh n62
