u-blox ANTARIS 4 - Page 70

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your position is our focus
4 N with On/Off Time
In FXNwith ffTimethereceive willonlystayonforT_on a raninitialfixhasbeen
a dswitchtoOffSt ards.
If signalwhe eiverwakesup,th re acquirea
q. If
t ccessfultherece atefor T_acq
.2.7.8 FX
contrasttousing outOn/O r fte
chievedan ateforT_offafterw
thereisnoGPS ntherec e ceiverwilltryto fixas
usualforT_ac
hisisnotsu ivergoestoOffSt _off.
signal OK
T_on
T_off
T_on
T_off
no signal
GPS Signal
lost
GPS
T_reacq
T_acq
T_acq
on off on off on off on
System
state
signal
T_acq_off
T_on
T_acq
time
off
First
Fix
First
Fix
First
Fix
T_off

Figure 57: FXN ff Time, GPS signal is lost in Full Power State
Ifthesignalislostduringtheon q,ifthisisnotsuccessful
estoOffStatefor ceivergoesto
OffStatefor .Afterthis
timetheGPSwillstarttoacquireSVasanormalstartup.
 t will never happen, because T_on overrules
T_reacq.
with On/O
time,thereceiverstartstoreacquiretheSVforT_reac
thereceivergo T_reacq_off.IfT_onisreachedbeforeT_reacqisexpired,there
T_off
Note If T_reacq is longer than T_on a reacquisition timeou
off on
signal OK
no signal
off on
time
GPS
signal
System
state
GPS Signal
lost
T_off
T_acq
T_acq_off
T_acq

Figure 58: FXN with On/Off Time, GPS signal is lost in Full Power State
GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) ReceiverDescription
GPS.G4-MS4-05007-A1
  Page 70