u-blox ANTARIS 4 - Page 91

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your position is our focus
Externaldatasource,e.g.wirelessnetworkoperator
Almanac
Ephemeris
Coarse Position
Coarse Time
Precise Time
Synchronization
Pulse
Cold Start
Improved to Improved to
typ 34 s
typ 24 s typ 4-12 s

Figu g Principal
lse”iftheoptionhardwaretimesynchronizationpulseisdesired.
3. Apply optional hardware time synchronization pulse within 0.5s after sending the AID-INI message if

hardwaretimesnyconizationisrequired.Beforeapplyingthetimepulse,allowtheGPSreceivertoparseand
processtheAID-HUImessage.Thetimeforparsingdependsonthebaudrate.Theprocessingtimeis100ms
maximum.
4. SendoptionalUBX-AID-HUI(health,UTCandionosphereparameters)message
5. SendoptionalUBX-AID-ALM(almanac)
message
UBX Aiding messages

re 75: Aidin
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Aiding Sequence
1. SendUBX-AID-EPH(ephemeris)message
2. SendUBX-AID-INI(time, clockandposition)message.Donot forgetto setthe‘Accurate timeis inputwith
timepu
Message Description
AID-REQ
VirtualAidingconfigurationmessagetoenableaidingrequestatstartup.
Ifthismessageisenabled,theAidingClientwillautomaticallypollaiding
datafromanAidingServerwithanAID-DATAmessageincaseofacold
start.
AID-DATA PollsallGPSInitialAidingData
AID-INI
Containsposition,time,clockdriftandvalidationparametersofthe
aidingdata.
AID-HUI
Containshealthbitmask,UTCtimeandKlobucharparameters.
ThismessageisnotrequiredtoachieveagoodTTFF,butithelpsto
achievegoodpositionaccuracyandtocorrecttheUTCoffset.
AID-ALM ContainsthealmanacdataofoneSV.
AID-EPH ContainstheephemerisdataofoneSV.
Table 26: Aiding messages
ForfurtherinformationabouttheUBXaidingmessages,refertotheANTARIS
®
4Protocol Specifications [9].
GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) ReceiverDescription
GPS.G4-MS4-05007-A1
  Page 91