ashtech GG Surveyor, Reference Manual

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32 GG Surveyor GPS+GLONASS Reference Manual
intentionally advanced or retarded). The data latency of this PBN message is
normally about 40 milliseconds after the 1PPS pulse.
Figure 4.7 shows the PPS characteristics. The PPS occurs when the signal goes high.
The PPS is generated exactly on the GPS second, and the pulse remains high for 1-2
milliseconds. The precision of the PPS signal is 70 nsec (nanoseconds) in stand-alone
mode, and 45 nsec in differential mode. A position must be computed for this
accuracy to be valid.
Figure 4.6: Relationship of GPS Time in PBN Record to 1 PPS Pulse
Figure 4.7: 1PPS Characteristics