u-blox ANTARIS 4 - Antenna and Antenna Supervisor

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your position is our focus
Example
Use on/off time
Enabled 
T_on [s]
0(=onevalidfix)
T_off [s]
86’400(=24hours)
Absolute align
Enabled
Base TOW [s]
43’200(=12hours)
T_acq [s]
60(=1minute)
T_acq_off [s]
120(=2minutes)
T_reacq [s]
5
T_reacq_off [s]
60
Operation
Thereceiverwillwakeuponceadayat12:00GPSandperformonepositionfix.
Table 17: Example settings FXN With On/Off Time and absolute Alignment
 Note If T_on is set to 0s, the receiver will enter Off State as soon as the PositionAccuracyis below the
P Accuracy Mask (see also Section 4.6.8.1). For an improved accuracy, increase T_on by a few
seconds.
The FixNOW™(FXN)screen in u-center AE software holds three templates (example parameter sets)
 basedon
theFixNOW™Mode(FXN),providinganinsighttothecapabilityofthisfeature.
1. Mobile Device Set: Setting with continuous GPS fixes as long as there is good sky view, but low
powersettings therwise(usingFXN without On/Off Time).
2. Asset Tracking Unit Set: Sleeping unit but allows position information on request (using FXN with
rnally Controlled Power Management
RealTimeClockStatusinUBX–MON(Status)–
d  whether the internal RTC is calibrated or not. A
ANTARIS
®
4GPSReceiversget theL1 bandsignalsfromGPSsatellitesata  nominal frequencyof 1575.42MHz.
TheRFsignalisconnectedtotheRF_INpin.
ANTARIS
®
4GPSmodulescanbeconnectedtopassiveoractiveantennas.
 Note ForANTARIS
®
4GPSreceivers,thetotalpreamplifiergain(minuscableandinterconnectlosses)must
notexceed50dB.Totalnoisefigureshouldbebelow3dB.
TheANTARIS
®
4Technologysupportseitherashortcircuitprotectionoftheactiveantennaoranactiveantenna
supervisorcircuit(openandshortcircuitdetection).ForfurtherinformationrefertoSection 4.3.2).
4.3.1 Passive Antenna
nna is located near electronic components; therefore care should be taken to reduce electrical

o
On/Off Time).
3. Schedule Fix Set: AsAssetTrackingUnitbutwithpositioninformationalignedtoafixtime(using
FXN with On/Off Time and absolute Alignment).
4. User Set: Isselectedassoonasanyofthepredefinedsettingsarechanged
4.2.8 Exte
Incaseofexternalpowercontrol,it’snecessarytomonitorthe
HW (Har ware Status). The Real Time Clock Status indicates
calibratedRTCisrequiredtoachieveminimalstartuptime(hotstart).
If
 the RTC is not calibrated the receiver would typically start up only within 20-30 s even if ephemeris data is
available.
4.3 Antenna and Antenna Supervisor
A design using a passive antenna requires more attention regarding the layout of the RF section. Typically a
passive ante
GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) ReceiverDescription
GPS.G4-MS4-05007-A1
  Page 72