
Strictly speaking,
amplitude
is an
instantaneous measure that may
take a positive or negative value.
Magnitude is
properly either an
absolute value, or a squared or
root mean square
(RMS) value
representative of amplitude over
some time interval. The terms are
often used interchangeably.
See
Linearity
on page 21.
Bracewell, Ronald N.,
The Fourier
Transform and its Applications,
Second Edition (New York:
McGraw-Hill, 1985).
Magnitude frequency response
To gain a general appreciation of aliasing, it is neces-
sary to understand signals in the
frequency domain.
The
previous section gave an example of inadequate ...