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Unformatted text preview: ld the transmission last if
10 000 7-bit characters
were sent across RS-232 operated at 9600
baud? The Nyquist Sampling Theorem
Theoretical limit on the maximum speed at which
data can be sent over an error-free (noiseless)
D = data rate in bit per second (bps)
B = bandwidth in hertz (hz) For a scheme that uses binary signals (two levels
Date Rate = D = 2B
For a scheme that uses K levels of signal
D = 2Blog2K Shannon’s Theorem
Shannon’s Deals with a noisy medium
Signal to noise ratio is the strength of the signal
compared to the strength of the noise = S/N
The signal to noise ratio is usually expressed in
decibels (db) = 10log10S/N
Maximum data rate on a noisy medium is:
D = B log2 (1 + S/N)
How fast data can be sent across a
voice telephone call? Telephone system: – Bandwidth =...
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This note was uploaded on 08/14/2011 for the course ELECTRONIC G52CCN taught by Professor Professorgail during the Spring '09 term at Uni. Nottingham.
- Spring '09