外文翻译外文文献英文文献IIR数字滤波器的设计

1、袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁

2、衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂

3、羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂

4、薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀

5、蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁

6、蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁

7、蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿

8、螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀

9、蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁

10、螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿

11、袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿

12、袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀

13、罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈

14、羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈

15、薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿

16、蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇

17、蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇

18、蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈

19、螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆

20、螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇

21、螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇

22、袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅

23、袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆

24、羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆

25、羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄

26、薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅

27、蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅

28、蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃

29、蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄

30、螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁荿袄肈膇莈羆袁蒆莇蚆肆莂莆螈衿芈蒅袀肄膄蒄薀袇肀蒃蚂肃蒈蒃袅羆莄蒂羇膁芀蒁蚇羄膆蒀蝿腿肂葿袁羂莁薈薁膈芇薇蚃羀膃薇螅膆腿薆羈聿蒇薅蚇袁莃薄螀肇艿薃袂袀膅薂薂肅肁蚁蚄袈莀蚁螆肄芆蚀罿袆节虿蚈膂膈蚈螁羅蒇蚇袃膀莂蚆羅羃芈蚅蚅膈膄莂螇羁肀莁衿膇荿莀蕿羀莅荿螁芅芁 莈艿薈罿芄艿蚁膄膀芈螃羇肆芇袅螀莅莆薅羅芁莅蚇螈膇莄衿羄膃莃蕿袆聿莃蚁肂莇莂螄袅芃莁袆肀腿蒀薆袃肅 iir digital filter design an important step in the development

31、 of a digital filter is the determination of a realizable transfer function g(z) approximating the given frequency response specifications. if an iir filter is desired,it is also necessary to ensure that g(z) is stable. the process of deriving the transfer function g(z) is called digital filter desi

32、gn. after g(z) has been obtained, the next step is to realize it in the form of a suitable filter structure. in chapter 8,we outlined a variety of basic structures for the realization of fir and iir transfer functions. in this chapter,we consider the iir digital filter design problem. the design of

33、fir digital filters is treated in chapter 10. first we review some of the issues associated with the filter design problem. a widely used approach to iir filter design based on the conversion of a prototype analog transfer function to a digital transfer function is discussed next. typical design exa

34、mples are included to illustrate this approach. we then consider the transformation of one type of iir filter transfer function into another type, which is achieved by replacing the complex variable z by a function of z. four commonly used transformations are summarized. finally we consider the comp

35、uter-aided design of iir digital filter. to this end, we restrict our discussion to the use of matlab in determining the transfer functions. 9.1 preliminary considerations there are two major issues that need to be answered before one can develop the digital transfer function g(z). the first and for

36、emost issue is the development of a reasonable filter frequency response specification from the requirements of the overall system in which the digital filter is to be employed. the second issue is to determine whether an fir or iir digital filter is to be designed. in the section ,we examine these

37、two issues first . next we review the basic analytical approach to the design of iir digital filters and then consider the determination of the filter order that meets the prescribed specifications. we also discuss appropriate scaling of the transfer function. 9.1.1 digital filter specifications as

38、in the case of the analog filter,either the magnitude and/or the phase(delay) response is specified for the design of a digital filter for most applications. in some situations, the unit sample response or step response may be specified. in most practical applications, the problem of interest is the

39、 development of a realizable approximation to a given magnitude response specification. as indicated in section 4.6.3, the phase response of the designed filter can be corrected by cascading it with an allpass section. the design of allpass phase equalizers has received a fair amount of attention in

40、 the last few years. we restrict our attention in this chapter to the magnitude approximation problem only. we pointed out in section 4.4.1 that there are four basic types of filters,whose magnitude responses are shown in figure 4.10. since the impulse response corresponding to each of these is nonc

41、ausal and of infinite length, these ideal filters are not realizable. one way of developing a realizable approximation to these filter would be to truncate the impulse response as indicated in eq.(4.72) for a lowpass filter. the magnitude response of the fir lowpass filter obtained by truncating the

42、 impulse response of the ideal lowpass filter does not have a sharp transition from passband to stopband but, rather, exhibits a gradual "roll-off." thus, as in the case of the analog filter design problem outlined in section 5.4.1, the magnitude response specifications of a digital filter

43、 in the passband and in the stopband are given with some acceptable tolerances. in addition, a transition band is specified between the passband and the stopband to permit the magnitude to drop off smoothly. for example, the magnitude of a lowpass filter may be given as shown in figure 7.1. as indic

44、ated in the figure, in the passband defined by 0, we require that the magnitude approximates unity with an error of ,i.e., .in the stopband, defined by ,we require that the magnitude approximates zero with an error of .e., for .the frequencies and are , respectively, called the passband edge frequen

45、cy and the stopband edge frequency. the limits of the tolerances in the passband and stopband, and , are usually called the peak ripple values. note that the frequency response of a digital filter is a periodic function of ,and the magnitude response of a real-coefficient digital filter is an even f

46、unction of . as a result, the digital filter specifications are given only for the range . digital filter specifications are often given in terms of the loss function, in db. here the peak passband ripple and the minimum stopband attenuation are given in db,i.e., the loss specifications of a digital

47、 filter are given by , . 9.1 preliminary considerations as in the case of an analog lowpass filter, the specifications for a digital lowpass filter may alternatively be given in terms of its magnitude response, as in figure 7.2. here the maximum value of the magnitude in the passband is assumed to b

48、e unity, and the maximum passband deviation, denoted as 1/,is given by the minimum value of the magnitude in the passband. the maximum stopband magnitude is denoted by 1/a. for the normalized specification, the maximum value of the gain function or the minimum value of the loss function is therefore

49、 0 db. the quantity given by is called the maximum passband attenuation. for 1, as is typically the case, it can be shown that the passband and stopband edge frequencies, in most applications, are specified in hz, along with the sampling rate of the digital filter. since all filter design techniques

50、 are developed in terms of normalized angular frequencies and ,the sepcified critical frequencies need to be normalized before a specific filter design algorithm can be applied. let denote the sampling frequency in hz, and fp and fs denote, respectively,the passband and stopband edge frequencies in

51、hz. then the normalized angular edge frequencies in radians are given by 9.1.2 selection of the filter type the second issue of interest is the selection of the digital filter type,i.e.,whether an iir or an fir digital filter is to be employed. the objective of digital filter design is to develop a

52、causal transfer function h(z) meeting the frequency response specifications. for iir digital filter design, the iir transfer function is a real rational function of . h(z)=moreover, h(z) must be a stable transfer function, and for reduced computational complexity, it must be of lowest order n. on th

53、e other hand, for fir filter design, the fir transfer function is a polynomial in : for reduced computational complexity, the degree n of h(z) must be as small as possible. in addition, if a linear phase is desired, then the fir filter coefficients must satisfy the constraint: t here are several adv

54、antages in using an fir filter, since it can be designed with exact linear phase and the filter structure is always stable with quantized filter coefficients. however, in most cases, the order nfir of an fir filter is considerably higher than the order niir of an equivalent iir filter meeting the sa

55、me magnitude specifications. in general, the implementation of the fir filter requires approximately nfir multiplications per output sample, whereas the iir filter requires 2niir +1 multiplications per output sample. in the former case, if the fir filter is designed with a linear phase, then the num

56、ber of multiplications per output sample reduces to approximately (nfir+1)/2. likewise, most iir filter designs result in transfer functions with zeros on the unit circle, and the cascade realization of an iir filter of order with all of the zeros on the unit circle requires (3+3)/2 multiplications

57、per output sample. it has been shown that for most practical filter specifications, the ratio nfir/niir is typically of the order of tens or more and, as a result, the iir filter usually is computationally more efficientrab75. however ,if the group delay of the iir filter is equalized by cascading i

58、t with an allpass equalizer, then the savings in computation may no longer be that significant rab75. in many applications, the linearity of the phase response of the digital filter is not an issue,making the iir filter preferable because of the lower computational requirements. 9.1.3 basic approaches to digital filter design in the case of iir filter design, the most common practice is to convert the digital filter specifications into analog lowpass prototype filter specifications, and then to t