3-30
Making Time Domain Measurements
Range
Range
In the time domain, range is defined as the length in time that a measurement can be made without
encountering a repetition of the response, called aliasing. A time domain response repeats at regular
intervals because the frequency domain data is taken at discrete frequency points, rather than continuously
over the frequency band.
where F is the spacing between frequency data points
For example:
Measurement range
1
F
------=
Measurement range
number of points 1–
frequency span Hz
-------------------------------------------------------------=
Frequency Span =
1 MHz
to 2.001 GHz
Frequency Spacing F 10 MHz=
Range
1
F
------
or
number of points
1–
frequency span
----------------------------------------------------------------
=
Range
1
10 10
6
------------------------= or
201 1–
210
9
----------------------
Electrical Length
range
the speed
of light
310
8
m
s
----
=
ElectricalLength 100
10
9–
s
3
10
8
m
s
----
=
ElectricalLength
30 meters
=