M ad e in Ge rm any
© Gigahertz Solutions GmbH
The ratio of minimum to maximum load of a cellular phone base
station usually is 1 to 4. At the time of measurement one does not
know the exact load. One way to overcome this is to measure dur-
ing low load periods (in the very early morning hours, e.g. from 3 to
5 am) and muliply the measurement by 4.
Special case: UMTS/3G and DVB-T: Measure 1 to 2 minutes
7
in
their incoming direction tilting the instrument slightly around it.
These special types of signals can sometimes be undervalued by
a factor of 5 by the analysers described here.
Special case: Radar for aviation and navigation. Radar beams are
emitted by slowly rotating antennas. Therefore they are only
measurable and “audio-analysed” every few seconds for millisec-
onds. This necessitates a special approach:
Set ”Signal“ to ”peak“. After a couple of radar beam passes read
out the highest number displayed. Because of the slow repetition
rate of the display necessary for all other measurements, the
numbers will vary considerably and will only be displayed for a
very short period of time. When using the HF38B set the switch
to ”Peak-hold“ and allow for several beam passes to establish
the equilibrium of charging and drooping, which may take a few
minutes.
Peak hol
Peak
Radar
Symbolic sketch
In most cases the measurement will be at the lower tolerance
band or in the extreme case even up to a factor of 10 too low
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.
For a simplified measurement of UMTS/3G-, DVB-T and Radar
without correction factors, Gigahertz Solutions offers the profes-
sional HF-Analysers HF58B-r and HF59B.
Limiting values, recommendations and
precautions
The ”Standard der baubiologischen Messtechnik“ (Standard for
Building Biology Measurements), SBM 2008, classifies measure-
ments (per radio communication service), with a note of caution
”pulsed signals to be taken more seriously than continuous ones“,
as follows:
Building Biology Recommendations as per SBM-2008
un-
conspicuous
moderately
conspicuous
very
conspicuous
extremely
conspicuous
Peak
meas-
µW/m²
< 0.1 0.1 - 10 10 - 1000 > 1000
© Baubiologie Maes / IBN
In fall 2008 the "Bund für Umwelt und Naturschutz Deutschland
e.V." (BUND) (environmental NGO) recommended a limiting value
of 1 µW/m² even for outdoor situations.
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Measurement will take longer because of the rapid fluctuations typical especially
for UMTS.
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Please note that there are also Radar systems operating in the higher Gigahertz
range.