u-blox ANTARIS 4, Руководство по системной интеграции

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4.7.2 Time Mode
This section only applies to LEA-4T modules.
LEA-4T modules support a special Time Mode for increased time accuracy. The AN
®
TARIS 4 is designed only for
stationary antenna setup.
is disabled, the receiver works like a
standard PVT receiver. If high timing accuracy is required and the fixed antenna position is not known, set the
Time Mode to ‘survey-in’. In this mode the ANTARIS
®
4 GPS receivers averages the position measurements over
a long period of time until a predefined standard deviation is achieved. Afterwards the receiver will be
automatically set to fixed Mode and the Timing features will be activated.
When the position of the fixed GPS Antenna is well known (i.e. surveyed position), set the Time Mode to ‘fixed
Mode’ and fill out X-, Y-, Z- Position parameter in ECEF including the standard deviation of the position.
The Time Mode features three different settings. When the Time Mode
Parameter Description
‘disabled’ Time Mode disabled (standard GPS positioning setting)
‘survey-in’
Time Mode activated, but the timing features are still inactive as the
current position is not yet defined/ known. When it’s measured
position is accurate enough, the receiver will be automatically set to
fixed Mode and the Timing features will be activated.
Time Mode
‘fixed Mode’ Time Mode activated and current position is defined
Survey-In
Minimum observation Time Minimum observation Time for activating timing features.
Required position standard deviation Required Standard deviation for activating timing features.
Fixed Time Mode True Position
X, Y, Z X-, Y-, Z- Position parameter in ECEF
Standard deviation Standard deviation of the fixed antenna position
Table 44: Time Mode Parameter description
-In’ can be found in UBX -. TIM (Timing) – SVIN (Survey-In).
Note Timing receiver also supports timing with only one SV. To allow it, change MinSV in UBX – CFG
The status information about ‘Survey
(Config) - NAV2 (Navigation 2) to 1.
GPS Modules - System Integration Manual (SIM) (incl. Reference Design) Receiver Description
GPS.G4-MS4-05007-A1 Page 113