These are displayed as vertical bars. The same rule as in our example applies
here, too: The higher the measured
signal strength
, the higher the bar. Further
information regarding each of the bars is displayed from left to right as
markers
in the upper display area. On the left,
marker 1
is displayed: (the first bar from
the left) with 942MHz at -63dBm. In the middle,
marker 2
(the second bar from
the left) 2.024MHz at -23dBm. On the right,
marker 3
(the last, rightmost bar) is
displayed: 5.823MHz at -42dBm.
Notice: The configured
frequency range
is constantly being scanned. Thus, the
display will also constantly change. This is recognizable because of a small dot
above the graphics display which moves from left to right. This procedure of con-
tinuous scanning is called
sweeping
.
So, what kinds of information have we acquired now?
1.) In the entire frequency range from 0-6GHz, there are 3 main signal sources.
2.) The frequency and signal strength of all 3 sources is exactly known.
So, we have acquired a quick overview of WHAT is active in this frequency
range.
As the exact frequency of the signal sources is now know, it is easy to
determine the exact applications emitting these signals (see also our fre-
quency tables on pages 64-65 or the more extensive frequency tables on
the Aaronia homepage).
On the basis of these frequency tables, we can determine for e.g. 942MHz:
937,6 to 944,8MHz = GSM 900 (DL) T-Mobile
meaning that this is a GSM900 celltower (DL=Download) of the provider
T-Mobile.
14.0 Spectrum analysis basics
50
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Summary of Contents for SPECTRAN HF-2025
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