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1.1.Electromagneticenvironment
Figure1.1:Themoduleoftheverticalcomponentoftheelectricfield|Ev|.
Thespectrumofusefulsignals–blueplot,byoperatinghanddrillingtool
–redplot
Obviously,thereisaninteractionbetweentheenvironmentanditems
embeddedinit.Ahumanbeingcanbeinfluencedbytheelectromagnetic
environmentthroughtheimpactonthehealthandundesiredtheftofelec-
tronicallyprocesseddata.
Cellulartelephonesareexampleoftheimpactoftheelectromagnetic
environmentonthehumanbeinghealth.Inthe90softhe20thcentury,when
thefirstgenerationofthecellulartelephonesbecamethemassconsumer
good,manycustomersobservedanxioussymptomsafterlongcalls.They
observedrednessandwarmingupoftheheadregionnexttothephone,
theyfeltphysicalandpsychotiredness.Alreadyatthistime,theresults
ofexperimentswithmonkeyswereknown.Theybehavedabnormallywhen
thetemperatureoftheirbrainswasincreasedby1deg.Itwasproved
veryrapidlythatthetemperatureofthehumanbrainincreasesmuchmore
extensivelybythecellularphonecall.Exemplarynumericalsimulationof
energyabsorptionbycellularphonecallisshowninFig.1.2.Thecolour
maprepresentsthevaluesofSAR.Theredishercolour,thebiggerSAR
value.
Themethodforquantificationoftheabilityofcellulartelephonesfor
warmingupthebraintissuewasworkedout.SpecificAbsorptionRate
SARwhichistheenergyabsorbedbythehumanbrainperunitmasswas
chosenasthequantificationparameter.ItismeasuredinW/m3.InFig.1.3
thesetupforSARmeasurementbycellularphonecallisshown.Itisbuilt
intheanechoicchamberlaidupwiththepyramidabsorptionmaterial.It
consistsofmouldofthehalfofhumanbodyfilledwithsolutionwithelectric
andmagneticpropertiessimilartohumanbrain.Beneath,thephoneunder
