´X¥G¦b©Ò¦³¦ÛµM¬Éªº°T¸¹³£¬O³sÄòªº¡A¦ý¬O¦b¹q¸£¥@¬Éªº°T¸¹¡A¥Ñ©ó³£¬O¥H¦ì¤¸¬°³æ¦ì¨ÓÀx¦s¡A©Ò¥H³o¨Ç°T¸¹³£¬OÂ÷´²ªº¡A²ºÙ¡uÂ÷´²®É¶¡°T¸¹¡v¡]Discrete Time Signal¡^¡A§Ú̳q±`¥i¥H±N³o¤@¦Cªº°T¸¹ªí¥Ü¦¨ x(nT)¡AT ¬O¨ú¼Ë¶g´Á¡An ¬O¾ã¼Æ¡AnT «h¥Nªí®É¶¡¡C¬°¤F²¤Æ°_¨£¡A§Ṳ́]¥i¥H¨Ï¥Î x[n] ¥NªíÂ÷´²®É¶¡°T¸¹¦b nT ªºÈ¡C¥H¤U±N¤¶²Ð´XÓ±`¨£ªºÂ÷´²®É¶¡°T¸¹¡C
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d[n] = 1, if n=0
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d[n] = 0, otherwise
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d[n-k] = 1, if n=k
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d[n-k] = 0, otherwise
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³æ¦ì¯ß½Ä°T¸¹¨ã¦³¡u¿z¿ï¡vªº¯S©Ê¡A¥ô¦ó°T¸¹ x[n]¡]n = -¡Û¡ã¡Û¡^»P d[n-k] ¬Û¼¡A´N¥u³Ñ¤U²Ä k ¶µ¡A¥i¥Î¼Æ¾Ç¦¡´yz¦p¤U¡G
x[k] = Sn=-¡Û¡Ûd[n-k]¡Ex[n]
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³æ¦ì¨B¶i°T¸¹¡]Unit Step Signal¡^¥u¦³¦b n >= 0 ®É¨äȬ° 1¡A¨ä¥L³£¬O¹s¡C¥i¥Î¼Æ¾Ç¦¡ªí¥Ü¦p¤U¡G
u[n] = 1, if n>=0
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u[n] = 0, otherwise
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Audio Signal Processing and Recognition (µ°T³B²z»P¿ëÃÑ)