User Guide

Table Of Contents

2013‐09‐27

NUR‐05WL2ImplementationGuidev1.1

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8 DIAGNOSTICFUNCTIONS

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8.1  REFLECTEDPOWERMEASUREMENTS

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Thismeasurementcanbeusedtocheckwhatisthematchingoftheantenna(s)andfeedline(s).Whenthis

function is triggered will NUR‐05WL2 module put carrier wave ON at full power and then measure the

absolutepowerlevel thatiscoming toreceiverport. Attenuation intheRX‐line is 11dBand fulloutput

power is 27 dBm. Based on these two values you can determine antennas return loss (S11) valueusing

formulabelow:

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Antennasreturnloss=Powertoantenna–(RX‐lineattenuation+reflectedpowermeas.)

Antennasreturnloss=27–11–(reflectedpowermeas.)

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When leakage cancelation is used these calculations are no longer absolute return loss values because

cancellationcircuitryeliminatessomeamountofthesignalreflectingbackfromtheantenna.Inthiscase

thisvalueistheabsolutepowervaluethatisleakingintothereceiverduetoimperfectcouplerisolationor

antennamismatch.

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8.2  CHANNELSCANNER

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Thisfunctioncanbeusedtomonitortheinterferencesinthecurrentfrequencyband.Itisalsousefulifyou

wanttocheckifsomefixedchannelisinuse.WhenyoutriggerthisfunctionNUR‐05WL2willscanallthe

channelsincurrentregionandreturntheRSSI‐valueofeachchannel.Returnedvaluesareabsolutepower

levelsinreceiver.LossbetweenRF_OUTpinandreceiveris11dBsoactualvaluesareabout11dBhigher.

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8.3  RECEIVEDSIGNALSTRENGTH(RSSI)

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WhenreadingatagNUR‐05WL2modulealsoreturnsreceivedsignalstrengthindicationvaluesifwanted.

Twovaluesarereturnedperonetag.Oneistheabsolutepowerlevel(dBm)andsecondisthescaledpower

levelvalueofthetagsbackscattersignal.NUR‐05WL2moduleautomaticallyadjustsreceiveraccordingto

outputpowerlevels.CausingthatmaximumandminimumabsoluteRSSIpowerlevelswillvarydepending

fromtheusedoutputpowerlevels.ThatiswhyscaledRSSIvalueisalsoavailable.Scaleis0–100.

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