HW V4 / © 2005 – 2013 Aaronia AG, DE-54597 Strickscheid
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Manual Spectran V4
Spectrum analysis basics
The different kinds of vehicles are called radio applications and have their
own abbreviations: e. g. the radio application “UMTS” (the new, digital mobile
communications standard) has its own frequency range which spans 1900 to
2200MHz (1.9 – 2.2GHz).
The speed at which the vehicles are travelling can now be replaced by a new
expression: the signal strength or level.
So far, we have now explained the used expressions and units. Now, high-
frequency analysis works just as our motorway example:
For example, our measurement device should evaluate all frequency ranges
from 1MHz to 6 000MHz (in pictures, our 6 000 m wide motorway). Step by
step, every frequency range is evaluated precisely. First: 0 to 1MHz, then
1MHz to 2MHz etc. until 6 000MHz. Also, the signal strength of every
frequency range is exactly stored. Like this, we also learn what signal
strength was present on which frequency range.
Real-world examples:
Let’s assume that we want to exactly evaluate the frequency range from
1GHz to 6GHz, and that the following 3 radio applications were active
simultaneously with various signal strengths (in practice it will mostly be a lot
more different applications.
Frequency range (MHz)
Application
Reading
1.880 – 1.900
DECT portable phone
40
2.320-2.450
Amateur radio (11cm)
20
5.725 – 5.825
WLan 802.11a
80
How can this be visually displayed on a measurement device? Well, first, we
will map the frequency range from 1GHz to 6GHz on a line from left to right
(X-axis):
1GHz__________ __________ ___________ __________ _________6GHz
Ok, this was still pretty simple. Now, we tag each of the 3 applications
depending on their frequency on the right spot of the X-axis and can thus see
where they can be found:
1GHz__________ __________ __________ __________ __________6GHz
