CHƯƠNG 2: TRUYỀN THÔNG ĐA PHƯƠNG TIỆN

Codeword: mỗi ký tự được biểu diễn bởi sự kết hợp duy nhất của 1 số cố định các bít nhị phân 7 bit được gọi là từ mã (Codeword)- (Từ mã là sự kết hợp duy nhất của 1 số cố định các bit nhị phân 7 bít) Analog signal: Tín hiệu có biên độ thay đổi liên tục theo thời gian Signal encoder: Bộ chuyển đổi từ tín hiệu tương tự sang dạng số được thực hiện bởi 1 mạch điện gọi là mã hóa tín hiệu Signal decoder: bộ chuyển đổi tín hiệu được lưu trữ dưới dạng số sang dạng tín hiệu tương tự thay đổi theo thời gian được thực hiện bởi mạch điện gọi là giải mã tín hiệu.

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L.-@KBC Image sensor: wKB; _;%9B,-.$C 4(!B&$[%?-AF#$.?!(-. C >9BKB_;90-.S1$3G -L2G$[%0! ( 8FO#$7L.?9E(!:)6(($ )66G((-@? ,L.!:$(' &_;9!:5S oKB€; L.-@89BKBG,L. &7$C 2.5 AUDIO 7-?)6*$-. $-L.$- 3 >TM#$ $--./Œ•we%•weG$--./%Œwe %•we 3 4I&-"!D#$ -.• L.#$*?-.~•  •$:1o 2312-.VB9h-6" M LA%)6Z12 2.5.1 PCM Speech (c;@$((*-8V$A,7_;;)$  FMV$?6?1P=4W27TM" C >TM#$,7A?/••wejG~we PoŽ!K&7$-.P--$$!Po Ž(K07$L.B0789 07$1LA07$:  2B89#$)6L.KBT`B!$-N" C 4A)6IL.-"DL.!$?&5SG$77 V$?aB89#$)6L.C=$7)60a!V$ 5SG7N-I-6-_7$!)8()60aC4? Y/0Y? L.S5G)6?I$#$S5$7 !L.?BaC 2.5.2 CD- quality audio (l-?78L.*$7<-@v$SC 4|SK*?7TI%Œwe•weI&-"!D-.~• C 4!8_;$"-&C 2.5.3. Synthesized audio 4"B(-?*$F-L.(!)C >9A-@(?7*$7"-ALAB?&ZGLK LY!I B: *$CW.$7\p R_$*$L. $9LA$ j. I)#$=!e$-.(!)1LAKc;2. )L.'*$CJFBIL.#$(!)-.. )L.I$-.( '*$c1L$S52MV$(KF-$ •% )"H8. )N?$%6cLK )"N?$% 0($C 4'-@c"  a -@(M6 9(KG.$ \ a R_$9?90$L.A7GO-.  (?-?LA$C=$: BLB0[97$C 4M6 onSn$[%!?(G7`('(6O6G\ (!\-?`('(M&-8V$6 4: *$EB--@L..6R*$ 1*$"-2C . 6%B<$FO 2 2 .2 SIGITIZATION PRINCIPLES (Nguyên tắc số hóa) P (  *)Q1Q$$-! 2 R$E"H9)6. Sb V max 20 log 10 (¿ ¿ V min ) ¿ > 2. 2.3 . Decoder design 7 I) DAC1S$-5$-L 2 *!-.'!:/)6&$)6