HW V4 / © 2005 – 2013 Aaronia AG, DE-54597 Strickscheid
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Manual Spectran V4
Spectrum analysis basics
10.3. Application of spectrum analysis
There are 2 main reasons for application of spectrum analyses
a. You would like to know which radio applications are active
b. You would like to measure the exposure caused by each of the radio
applications separately, e. g. for evaluating exceeding of exposure limits.
Regarding a.:
Let’s reconsider our “giant motorway” example:
Remember that every lane was only intended for use by a single kind of
vehicle. Now imagine that a huge bridge crossed this motorway, with you
standing on the bridge and looking down on the motorway.
Now, for example, you would like to know exactly what is happening on the
motorway, and this for every single lane. However, the motorway is
incredibly wide, so you would need rather good binoculars to be able to even
look a few km far. Let’s just imagine that your binoculars have a range of
6km (6000m). Now you would like to know how much traffic there is on a
specific lane and how fast it is travelling. So, you’ll take a piece of paper and
write down the number of the lane and the data you evaluated. Starting at
lane 1, you see: nothing – OK, let’s go on with lane 2 – nothing either. Now
lane 3 – OK, there is some traffic going at 18 km/h. Continuing with lane 4 –
Nothing, etc. Until you have reached the last lane. What have you
accomplished now? You’ve performed an analysis of the entire range of
lanes from 0 – 6 km. Or, in other words: You performed a range analysis. As
you know, to analyze something means breaking it down into smaller parts
which can be evaluated. In this case, the 6 km wide motorway was that big
“something” and the smaller parts were the individual lanes. The word “range”
can now be replaced by the word “Spectrum” and there we are. You have
performed a spectrum analysis.
If you now in addition have a lanes plan telling you which lane is assigned to
which kind of vehicle, you can exactly determine what kinds of vehicles have
just been travelling.
Spectrum analysis in high frequency technology works exactly like that:
There are „lanes“, here as well. Though, these lanes are called frequency
ranges. The width of these frequency ranges is measured in the unit Hz
(Hertz). However, as the frequency ranges are mostly found in high Hz
ranges. Writing them in plain Hz would require huge numbers. Thus, the unit
Hz is often extended to MHz (1.000.000Hz) and GHz (1 000 000 000Hz).
Like this, the whole thing becomes much clearer. So, 1 000 000 000Hz can
also be written as 1 000MHz or 1GHz.
