¹ï©ó¥ô¤@ÓÂ÷´²®É¶¡°T¸¹ x[n] ¦Ó¨¥¡A§ÚÌ¥i¥H¨Ï¥Î¤@Ó¹q¸£¨t²Î¨Ó³B²z¦¹°T¸¹¡A±o¨ìªº¿é¥X¬° y[n]¡A³oÓÃö«Y¥i¥H¥Î¼Æ¾Ç¦¡ªí¥Ü¦p¤U¡Gy[n] = L{x[n]} ´«¥y¸Ü»¡¡A¦¹¨t²Î L{¡E} ªº¿é¤J¬O¤@Ó¨ç¼Æ x[n]¡An = 0¡ã¡Û¡A¦Ó¹ïÀ³ªº¿é¥X¤]¬O¤@Ó¨ç¼Æ y[n]¡An = 0¡ã¡Û¡C¦pªG L{¡E} º¡¨¬¤U¦C¨âÓµ¥¦¡¡A¦¹Ãþ¨t²ÎºÙ¬°¡u½u©Ê¨t²Î¡v¡]Linear Systems¡^¡G
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- y[n] = L{x[n]} ¡÷ ky[n] = L{kx[n]}
- y1[n] = L{x1[n]}, y2[n] = L{x2[n]} ¡÷ y1[n] + y2[n] = L{x1[n] + x2[n]}
y1[n] = L{x1[n]}, y2[n] = L{x2[n]} ¡÷ ay1[n] + by2[n] = L{ax1[n] + bx2[n]}, for all a and b. ¤Wzµ¥¦¡ºÙ¬°¡uÅ|¥[ì«h¡v¡]Superposition Principle¡^¡A´«¥y¸Ü»¡¡A¥unº¡¨¬Å|¥[ì«hªº¨t²Î¡A´N¬O½u©Ê¨t²Î¡C¦pªG L{¡E} º¡¨¬¤U¦Cµ¥¦¡¡A¦¹Ãþ¨t²ÎºÙ¬°¡u«D®ÉÅܨt²Î¡v¡]Time-invariant Systems¡^¡G
y[n] = L{x[n]} ¡÷ y[n-k] = L{x[n-k]}, for all k. ¦pªG¤@Ó¨t²Î¬O½u©Ê¡A¦Ó¥B¤]¬O«D®ÉÅÜ¡A§Ú̺٨䬰¡u½u©Ê«D®ÉÅܨt²Î¡v¡]Linear Time-invariant Systems¡^¡A²ºÙ LTI ¨t²Î¡C¦b¥H¤Uªº°Q½×¤¤¡A§Ú̧¡°²³]§ÚÌ©Ò¹J¨ìªº¨t²Î³£¬O LTI ¨t²Î¡C
Audio Signal Processing and Recognition (µ°T³B²z»P¿ëÃÑ)