求傅里叶变换过程.pdf

姹傚崌浣欏鸡鑴夊啿鐨勫倕閲屽彾鍙樻崲 2肀 sinc(2肀 肀?cos鈦?2饊寢饊€卷睋 肀? 0 0 0 ( ) 肀 肀 = 2 1鈭 (4饊€卷睋 肀? 0 ( ) 鍙互鍒╃敤鍌呴噷鍙跺彉鎹㈤鍩熷嵎绉畾鐞嗭紝鍗虫椂鍩熺浉涔橈紝棰戝煙鍗风Н銆傛垜浠皢肀 肀 鍒嗚В涓 ( ) sin 2饊寢肀 肀 0 ( ) ( ) 肀 肀 = 2肀 sinc 2肀 肀 = 2肀 = 2肀 肀狆€亷(2饊寢肀 肀? 1 0 0 0 2饊寢肀 肀 0 0 0 ( ) 肀 肀 = cos鈦?2饊寢饊€卷睋 肀? 2 0 1 1 1 1 ( ) 肀 肀 = = ( + ) 3 1鈭 (4饊€卷睋 肀?2 2 1鈭?饊€卷睋 肀 1+4饊€卷睋 肀 0 0 0 = 1 ( 1 1 鈭 1 1 ) 8饊€卷睋0 肀 + 肀 鈭 4饊€卷睋0 4饊€卷睋0 杩欎竴闇€瑕佺敤鍒板父鐢ㄥ倕閲屽彾鍙樻崲瀵 | | AW 饊€粹仭, 饊寯 鈮 饊亰 ( ) ( ) ( ) 鍙樻崲瀵?锛氻睌 肀 = 肀狆€亷 饊亰肀 ~戆 饊寯 = { 1 1 饊寢 | | 0鈦? 饊寯 饊亰 ( ) ( ) ( ) ( ) ( ) 鍙樻崲瀵? 锛氻睌 肀 = cos 饊亰肀 ~戆 饊寯 =饊寢[饊嬁 饊寯 鈭掟€亰 +饊嬁 饊寯 +饊亰 ] 2 2 1 鈭掟€仐饊寢鈦?饊寯 0 ( ) ( ) ( ) 鍙樻崲瀵? 锛氻睌 肀 = ~戆 饊寯 =饊仐饊寢肀犿睌饊仜 鈭掟€寯 = { 3 3 饊仭 鈦♀仭