Table9
RecommendedGPS/GLONASSAntennaSpecifications(Cont.)
Requirement / Recommendations
OperatingTemperature 0°Cto+40°C(Recommended)
Cable length requirements
ThelimitonthelengthoftheGPScabledependsonmultiplefactors:
•
LocationoftheGPSantenna.
•
TypeoftheRFGPScableused.
•
Splittersandconnectorsused.
Lengthsvarybasedontheaboveparameters.Theparameter,definingpropercable
length,isthesignalstrengthattheinputsofthePicoGPSreceiver.Thesignalstrength
mustmeetthesensivityrequirementsasshowninthetablebelow.
Table10
GPSsensitivityrequirements
Parameter Action type Sensitivity
GPSSensitivity
*
Tracking -161dBm
HotAcquisition -161dBm
ColdAcquisition -147dBm
Reacquisition -161dBm
*-Valuesarevalidatroomtemperature25
o
C[77
o
F]
External GPS Antennas
ManydifferentGPSantennaoptionsareavailableforanoutdoorGPSantenna.The
guidelinesinTable9:RecommendedGPS/GLONASSAntennaSpecificationsalso
applytoanexternalGPS/GLONASSreceiver.TheFlexiZoneMicroGPSantenna
(473100A)cansuitthispurpose.Thisantennaisdesignedtomountdirectlytothe
femaleNconnectorontheFZMsodoesnotincludeacableormountingfeature.A
mountingbracketwouldbeneededwithabulkheadfemaleNconnectorthenalongrun
ofcable.IfadeploymentofalargenumberofFZPsisneededwithremoteGPSthenthe
bestsolutionwouldbeasingleGPSantennaandadistributionnetwork.Caremustbe
takentoinsuretheDCblockisinplace.ThisDCblockcanbeaseparateitemor
includedinthedistributionnetwork.
Distribution networks
InthecaseoflargeindoordeploymentsofFZPunitsutilizingGPS/GLONASSitisbetter
touseasingleGPSantennawithadistributionnetwork.Thisequipmentisnotsupplied
byNokiaasitissitespecific,butcanbeusedtoovercomethelossesincurredwithlong
cablerunsandmultiplesplitstoaccommodateseparatefeedsintoeachFZP.Caremust
betakenwhenselectingtheproperdistributionamplifier.Thekeyrequirementsareas
follows:
•
ActiveGPS/GLONASSantennabias:Theamplifiermustprovide5VDCforthe
activeantenna.
•
PortImpedance:Allports(IN/OUT)mustbe50ohms.
Synchronization FlexiZoneIndoorPicoBTSProductDescription
22 DN09210454 Issue:01