u-blox ANTARIS 4 - RTCM Protocol

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your position is our focus
4.4.4.2 NMEA Protocol Configuration (UBX – CFG – NMEA)
TheNMEAprotocolonANTARIS
®
4receiverscanbeconfiguredtotheneedofcustomerapplications.Asdefault
all invalid position and all positions out of the defined accuracy range are not reported (details see Section
4.6.9.1).
Parameter Description
NMEA Filtering

 Positionfiltering
Ifdisabled,invalidoroldpositionoutputisbeingcommunicated,butthe
validflagindiciatesthatthedataisnotcurrent.
 Maskedpositionfiltering
Ifdisabled,Maskedpositiondataisstillbeingoutput,butthevalidflagwill
indicatethatthedefinedaccuracyrangehasb enexceeded.e
 Timefiltering
Ifdisabled,thereceiver'sbestknowledgeoftimeisoutput,eventhoughit
mightbewrong.
 Datefiltering
Ifdisabled,thereceiver'sbestknowledgeofdateisoutput,eventhoughit
mightbewrong.
 SBASfiltering
Ifenabled,
SBASsatellitesarereportedaccordingtotheNMEAstandard.
 TrackFiltering Ifdisabled,anunfilteredCOGoutputisbeingoutput.
NMEA Version
TherearetwoNMEAstandardssupported.ThedefaultNMEAprotocol
versionis2.3.AlternativelyalsoSpecificationversion2.1canbeenabled(for
detailsrefertoSection 4.6.9.1).
NUM SV
ThisistheMaximumNumberofSVsreportedinNMEAprotocol.Thisdoes
notaffectthereceiver'soperation.ItonlylimitsthenumberofSVsreported
inNMEAmode(thismightbeneededwitholdermappingapplications
whichonlysupport8-or12-channelreceivers).
NMEA Flag

 CompatibilityMode
SomeNMEAapplicati
decimalcomma.Th
onsonlyworkwithafixednumberofdigitsbehindthe
ereforeANTARIS
®
4offeracompatibilitymodeto
communicatewiththemostpopularmapapplications(e.g.NOKIAphone,
TOM-TOMreceivers).
 ConsiderationMode
ANTARIS
®
4usesasoph qualitydetectionscheme,inorderto
allSV
ifit
IfConsiderationmodeisenabled,allSatellites,whichwereconsideredfor
municatedasbeingusedfortheposition
tellitesare
inedinthe
isticatedsignal
producethebestpossiblepositionoutput.Thisalgorithmconsiders
measurements,andeventualldecidestoonlyuseasubsetthereof,
improvestheoverallpositionaccuracy.
navigation,
arebeingcom
determination.IfConsiderationmodeisdisabled,onlythosesa
markedasbeingused,whichaftertheconsiderationsteprema
positionoutput.
4.4.5 RTCM Protoco
T Technical tocolisaunidirectionalprotocol(inputtothe
r pplying the GP rrection data (DGPS). The RTCM protocol
specificationisavailablefrom
http://www.rtcm.org/.
TheANTARIS
4GPSTechnologysupportRTCMCorrectionTypeMessages1,2,3and9.
l
heRTCM(Radio CommissionforMaritimeServices)pro
eceiver) su S receiver with real-time differential co
®
GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) ReceiverDescription
GPS.G4-MS4-05007-A1
  Page 88