作业答案9 10章

1、“鬥T H %丹）H伙严）Let 心pfuM d denote rhe passbaiul find 引opb日nd npples oflespecrively. Also, krJ=26 and 吞$ 二 denote rlie p assbaiid and 引 op band ripple $ of 人 respecTiclVr rTThen 存卩、三 1 一（ 1 一 存戸）：and 占亍丄=（心 J - For a cascade of 4/ sections, 勺皿=l-（l-6pand S =4严9.3G（） =or equivnlently, G（昌加*）-（討。）9.16 Fo

2、i no aliasing T 三.Fieiiie below shows the iiiagiiimde responses of rhe digital filteis Q./!（;） andJI3-n ;plot, (w/pi, 2 0*logl0 (abs (h) ) ;grid;zlabel(omega/pi); ylabel(Gain, dE);(a) Given; = 0.42t,= 0.5St 占” =0.002, g = O.OOS.Thus: Aw =06开，ofj = -201oioQt = 41.93 dB.Fiom Table 10.2, we see rliar f

3、bi fixed-window ftuicrions, we can achieve The luiniinmn stopband ntteiuiatioii by using Hniui, Ha nulling, oi Bbckniaii wijidows. Hann will have tlie lowest filter lengrlrSiiKe M= 1943, Nh仙=口财 +1卜也UTThe coiiespoudiiia lieqiiency rispcuise, geneiated with the code, ii sliowii below:The coiTespondiii

4、a frequency response, generated with the code, is shown below;(b) Given:=0.65;rxo =076jt,6” =0.002,6$ = 0.004.a$ = -201ogo6$ = 47.95 dB.From Table 10.2. we see that for fixed-window fiuictions, we can achieve the luininiuin stop band attenuation by using Hann, Haiiuniiis. or Blackman windows. Hanii will have the lowest filter length:Since M = 28.27, N叭,、=2M + 11= 59.The cones p