Digital Signal Processing Reference
In-Depth Information
signal has roughly the same shape as the original (analog) signal, dierences are
noticeable. Here we simply connected the points, though other (better) ways do
exist to reconstruct the signal.
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Figure 1.5: Three ways of viewing a signal.
It is possible to convert from analog to digital, and digital to analog. Analog
signal processing uses electronics parts such as resistors, capacitors, operational
ampliers, etc. Analog signal processing is cheaper to implement, because these
parts tend to be inexpensive. In DSP, we use multipliers, adders, and delay elements
(registers) to process the signal. DSP is more exible. For example, error detection
and error correction can easily be implemented in DSP.
1.4
What Is a System?
A system is something that performs an operation (or a transform) on a signal.
A system may be a physical device (hardware), or software. Figure 1.6 shows an
abstraction of a system, simply a \black box" that produces output y[n] based upon
