Communication Signal Design Lab.


송홍엽 교수의 잡글


2004.04.13 06:18

송홍엽 조회 수:17904 추천:180

In 1948. Claude Shannon, then a young engineer working at Bell Telephone Laboratories in Murray Hill, M.J., published a landmark paper titled “A Mathematical Theory of Communication.” In that paper, Shannon defined what the once fuzzy concept of “information” meant for communications engineers and proposed a precise way to quantify it : in his theory, the fundamental unit of information is the bit.
Shannon showed that every communications channel has a maximum rate for reliable data transmission, which he called the channel capacity, measured in bits per second. He demonstrated that by using certain coding schemes, you could transmit data up to the channel’s full capacity, virtually free of errors-an astonishing result that surprised engineers at the time.
   “I can’t think of anybody who could ever have guessed that such a theory existed,” says Robert Fano, an emeritus professor of computer science at the Massachusetts Institute of Technology, in Cambridge, and a pioneer in the information theory field. “It’s just an intellectual jump; it’s very profound.”
   The channel capacity became an essential benchmark for communications engineers, a measure of what a system can and cannot do, expressed in many cases by the famous formula, C=Wlog2(1+P/N). In the formula, C is the capacity in bits per second, W is the bandwidth in hertz, P is the transmitter power in watts, and N is the noise power, also in watts.
   From space probes to cellphones and CD players, Shannon’s ideas are invisibly embedded in the digital technologies that make our lives more interesting and comfortable.
   A thinker, juggling enthusiast, and exceptional chess player, Shannon was also famous for riding the halls of Bell Labs on a unicycle. He died on 24 February 2001, at age 84, after a long battle with Alzheimer’s disease. –E.G. 송홍엽: IEEE Spectrum 2004년 3월호에서 발췌한 글입니다...  -[04/12-22:48]- 박재석: Bell Lab은 New Jersey에 있다고합니다. Murray Hill, M.J -> N.J  -[10/13-22:07]-
번호 제목 글쓴이 날짜 조회 수
공지 논문에 영어작문 주의사항 몇 가지 송홍엽 2008.05.22 9042
공지 젊은 학부생 여러분에게... 송홍엽 2008.11.20 6005
공지 우리학과 대학원생 모두에게 (특히, 박사과정들에게) 하고싶은 말입니다. 송홍엽 2014.01.20 7074
88 basis란.. (and Online-HW2) 송홍엽 2003.10.06 77539
87 [펌]Turbo code에 대한 글 송홍엽 2004.04.13 43793
86 글 잘 쓰는 이공계가 성공한다 송홍엽 2008.05.22 24904
85 Dr. Shannon 송홍엽 2003.12.07 22239
84 Outlook Express Backup [1] 송홍엽 2006.03.04 21925
» SHANNON : CRACKING THE CHANNEL file 송홍엽 2004.04.13 17904
82 [교양상식] 메르센 소수--Mersenne Prime 송홍엽 2004.04.13 17413
81 교재준비작업(1) 송홍엽 2004.10.03 14148
80 벡터공간이란 무엇일까.. 송홍엽 2003.10.06 14020
79 funny story 송홍엽 2004.04.01 13937
78 채널코딩 둘째이야기... 송홍엽 2003.11.12 12659
77 하다마드 행렬에 대해서 (part 1) [1] 송홍엽 2003.10.06 10334
76 [펀글]수학의 open problems 모음. 송홍엽 2008.07.30 8768
75 대학원생 생활 가이드 [퍼온글] 송홍엽 2007.10.11 8345
74 아날로그 신호와 디지털 신호 송홍엽 2004.08.06 8268
73 [펀글] 추장의 선언 [1] 송홍엽 2008.02.22 7843
72 수학사 바로잡기 (2) 송홍엽 2008.06.03 7746
71 유클리디안 n차원 벡터공간 (and Online-HW1) 송홍엽 2003.10.06 7421
70 수학사 바로잡기 (1) - 오일러의 36명 장교문제와 조선시대 최석정 (수정본 - 일부 오류 수정) [1] file 송홍엽 2008.06.03 7102