Composite signal - a combination of sine waves with different frequencies, phases(the position of the wave at time 0) and amplitudes.
Bandwidth - the difference between the highest and lowest frequencies contained in that signal (the higher bandwidth, send faster)
log2L = N
L - number of level
N - number of bits that can send in period
8 Kbps - 8 kilo bits per sec
8 KBps - 8 kilo byte per sec
1 byte - 8 bits
Baseband transmission - use full capacity of channel to send data
low-pass channel - lowest frequency is 0
wide bandwidth - very high frequency
narrow bandwidth - not high frequency(send data very slow)
Bandpass channel - don't have to start from 0(the lowest can be any number, include 0)
Medium
analog bandwidth - hertz
digital bandwidth - bits per second
Nyquist Bit Rate
Bitrate = 2 * bandwidth * log2L
L = the number of signal level used to represent data
Shannon Capacity
capacity = bandwidth * log2(1 + SNR)
SNR = Signal to Noise Ratio
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