ZED-F9P-Integration Manual
UBX-18010802 - R02
4 Receiver description Page 59 of 114
Advance Information
Figure 36: Timepulse
4.10.2 Recommendations
• The time pulse can be aligned to a wide variety of GNSS times or to variants of UTC derived
from them (see the chapter on time bases). However, it is strongly recommended that the
choice of time base is aligned with the available GNSS signals (so to produce GPS time or
UTC(USNO), ensure GPS signals are available, and for GLONASS time or UTC(SU) ensure the
presence GLONASS signals). This will involve coordinating that the setting of CFG-SIGNAL-*
configuration group with the choice of time pulse time base.
• When using time pulse for precision timing applications it is recommended to calibrate the
antenna cable delay against a reference-timing source.
• Care needs to be given to the cable delay settings in the receiver configuration.
•
In order to get the best timing accuracy with the antenna, a fixed and accurate position is needed.
• If relative time accuracy between multiple receivers is required, do not mix receivers of different
product families. If this is required, the receivers must be calibrated accordingly, by setting cable
delay and user delay.
• The recommended configuration when using the UBX-TIM-TP message is to set both the
measurement rate (CFG-RATE-MEAS) and the time pulse frequency (CFG-TP-*) to 1Hz.
Since the rate of UBX-TIM-TP is bound to the measurement rate, more than one UBX-TIM-
TP message can appear between two pulses if the measurement rate is set larger than the
time pulse frequency. In this case all UBX-TIM-TP messages in between a time pulse T1 and
T2 belong to T2 and the last UBX-TIM-TP before T2 reports the most accurate quantization
error. In general, if the navigation solution rate and time pulse rate are configured to different
values, there will not be a single UBX-TIM-TP message for each time pulse.
The sequential order of the signal present at the TIMEPULSE pin and the respective output
message for the simple case of 1 pulse per second (1PPS) and a one second navigation update rate
is shown in the following figure.
To Next Page
Loading...
Need help?
General
