Alcoma ZENITH 80 - TX Power Regulation Methods

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MicrowaveradiorelaylinkZENITH80 
 9/52 1.2
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Thedemodulatedsignalgoesfromthemodemtoamuldex,whereuserdata(Ethernet)areseparated
from the diagnostic data. The user data are sent to the protected terminal box again through the
overvoltageprotectionbyaconnectioncablewith4pairsofconductors.
ThevoltageontheRSSIconnector
(
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figure6)isproportionatetotheintensityofthesignalreceivedfromtheoppositestation.Thisvoltage
determinestheheightofthe tone fortheacoustictransformerthatservesasanindicatorduring pointing
ofthelink.
2.1 TXPOWERREGULATION
The output power is set by manufacturer in conformity with maximum EIRP power condittions. EIRP
calculates with both Tran smitter output bower and antenna gain. There are two different concepts of
ZENITH80linkoutputpowerregulationconcept:
1. The basic possibility is to set output power from maximum 20 dBm in
 steps of 1 dB and 20 dB
rangewithkeepingitstimeandtemperaturestability.Itispossibletosettheoutputpowerfrom
theASDdiagnosticprogram.Thepowerisregulatedanddisplaidbasedoninf o rmation fromlocal
transmitter.MicrowavepartofODUisequippedwithbranchwheretransmittedoutput
detection
circuit with microwave diode resides. Detected value is used both for Tx power regulation and
displaying.
2. Advanced function ofATPC (automatic transmit power control)is basedon regulation of output
poweraccordingtotheconditionsofelectroma gneticwavespropagation.Itdecreasestheoutput
powerduringoptimalconditionsandminimizes
possibilitiesofinterferenceswithotherlinks.The
power is regulated to the certain selected level based on receiver signal level from the remote
station.
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