cs230 - 06
DESCRIPTION
CS230 - 06TRANSCRIPT
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. f(t), .
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f = 1/T- T- an, bn- n- c-
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b 01100010.
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: . 0 fc. (bandwidth). , .
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. ( 1MHz 3100Hz).
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b , 8 8/b . b/8Hz. 0 3000Hz, 3000/(b/8) = 24000/b.
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1924. . 1948. . H, 2H .
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V , : (b/s) = 2Hlog2V. , S V, S/N. 10log10(1 + S/N) (dB).
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H S/N: (b/s) = Hlog2(1 + S/N) (dB).
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. . (twisted pair). 1988. 3. ( 4 , 16MHz ). 1988. 5. ( , 100MHz ). 6. 7. ( 250MHz, 600Hz).
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. UTP (Unshielded Twisted Pair).
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.50 .70 , .
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. , . 1, 0. .
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( ). , ( 100km 50Gb/s).
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. 1865. , 1887. . 3108m/s 2/3 .
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, f = c