u-blox ANTARIS 4 - Page 69

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your position is our focus
4 out On/
In ,the receiverwi is good – neverturnit off.Ifthereislossof
s  is no signa r-up, the receiver il  go to an O r a predefined
p
T
itiontime) and acq_off (off timeafteran u sition)de the startup behavior
a . This can be an initial startup or a subsequent startup  after an unsuccessful reacquisition
proc
T reacq_off configure the reacquisition procedure aftera GPS signal loss. If
t
to
O
.2.7.7 FXN with Off Time
this mode ll –aslongasthere GPScoverage self
ignal, or if there l at powe w l time out and ff State fo
eriod.
_acq
(acquis T_ nsuccessfulacqui fine
fter an off time
edure.
_reacq (reacquisition time) and T_
heGPSsignalis
lost,thereceiver triesduring T_reacq toreacquirethesignal.Ifthisfails, thereceivergoes
ffStateforT_reacq_off. Afterthistimethereceiverwillstartupasdefinedabove.
GPS signal lost
signal OK
GPS
signal
no signal signal OK
time
T_reacq
T_reacq_off
T_acq
time-
outs
System
state
on onoff

Figure 56: FXN without On/Off Time, GPS signal is lost in Full Power State

Example
Useon/offtime Disabled 
T_on[s] NotusedT_off[s] Notused
Absolutealign DisabledBaseTOW[s] Notused
T_acq [s]
60
T_acq_off [s]
120
T_reacq [s]
5
T_reacq_off [s]
60
Operation
AslongasthereisgoodGPScoverage,thereceiverwillkeeprunning.
Ifthereislossofsignalforatleast5seconds,thereceiverwillshutdownfor60seconds.Afterthatofftime,
thereceiverwilltrytofindthesignalfor60seconds.Ifthatfailsit
willshutdownforanother120seconds.
Table 15: Example settings FXN without On/Off Time
GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) ReceiverDescription
GPS.G4-MS4-05007-A1
  Page 69