UC-00-M24 EN R2
Common Configuration
Commands
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5.1
High Precision Timing Setting
High precision timing is based on the fixed position (i.e., the receiver antenna is installed
in a fixed position) to provide a stable and reliable timing output. UT4B0 supports three
timing modes: fixed-location timing, optimized-location timing, and positioning timing.
UT4B0 module is configured to the optimized-location timing mode by default.
Fixed-location timing
Fixed-location timing mode is only suitable for static applications. In this mode, users
need to input the accurate center position of the receiver antenna. UT4B0 calculates the
distance between the antenna and the satellite, based on the accurate position manually
input by the user, and reckons the local time to perform timing service.
For static timing applications, this mode provides the best timing accuracy. As it is not
necessary to calculate its own position, the timing algorithm can screen out the satellites
with low elevation and weak SNR and those may be affected by multi-path signals to the
greatest extent, to reduce the influence of these adverse factors on timing accuracy. The
precision of antenna position may also directly affect the timing performance of this
mode. In general, to avoid a significant impact on timing accuracy, the accuracy of the
antenna position provided should be higher than 1 meter.
Optimized-location timing
Optimized-location timing mode is the extension of the fixed-location timing mode. In
this mode, UT4B0 first determines the antenna position after it is powered on. The
receiver collects a certain number (observation time) of positioning points and
calculates the average of these positioning points to obtain an accurate estimation of
the antenna position. Then it locks the position and switches to fixed-location timing
mode based on the locked position.
The observation time can be set, and its length determines the accuracy of the optimized
location. In general, it is recommended to set the observation time to at least 2 hours
(7,200s) to obtain position estimation with sufficient accuracy. The position calibration is
carried out after UT4B0 is installed and the position optimization is completed, and the
timing mode in the receiver setting will automatically switch to fixed-location timing
mode. When restarted, the receiver will re-optimize the position.
Positioning timing
In this mode, UT4B0 calculates the antenna position and time in real time, and calculates
the local time. It is the only mode to support dynamic timing. But due to the impact of
