Forouzan Chapter 3 Identification Flashcards
Data must be transformed to __ to be transmitted.
electromagnetic signals
Data can be _. _ are continuous and take continuous
values. __ have discrete states and take discrete values.
analog or digital,Analog data,Digital data
Signals can be _. _ can have an infinite number of
values in a range; _ can have only a limited number of values.
analog or digital,Analog signals,digital signals
In data communications, we commonly use _ analog signals and _digital signals.
periodic,nonperiodic
Frequency and period are the _ of each other.
inverse
_ is the rate of change with respect to time.
Frequency
_ describes the position of the waveform relative to time O.
Phase
A complete sine wave in the time domain can be represented by one single spike in
the _ domain.
frequency
A single-frequency sine wave is not useful in data communications; we need to
send a _, a signal made of many simple sine waves.
composite signal
According to _, any composite signal is a combination of simple
sine waves with different frequencies, amplitudes, and phases.
Fourier analysis
The _ of a composite signal is the difference between the highest and the
lowest frequencies contained in that signal.
bandwidth
A _ is a composite analog signal with an infinite bandwidth.
digital signal
Baseband transmission of a digital signal that preserves the shape of the digital
signal is possible only if we have a _ with an infinite or very wide
bandwidth.
low-pass channel
If the available channel is a _, we cannot send a digital signal
directly to the channel; we need to convert the digital signal to an analog signal
before transmission.
bandpass channel
For a noiseless channel, the _ defines the theoretical maximum
bit rate. For a noisy channel, we need to use the _ to find the
maximum bit rate.
Nyquist bit rate formula,Shannon capacity
