Trimble Outdoors Part Number 45005-00-ENG Removing the Quantization Error from the PPS Output

System Operation 5

Figure 5-2 illustrates the result of removing the quantization error from the PPS output in a user system.

The top plot shows the offset of the PPS output pulse relative to a stable standard such as a Cesium atomic clock. The quantization error is responsible for the jagged appearance of the waveform.

The middle plot shows the quantization error as reported by the Acutime 20000 in packet 0x8F-AC.

The bottom plot is the result of subtracting the quantization error from the PPS offset.

	100
(ns)	50
Offset	0
PPS	-50
	-1000
(ns)	100
Error	50
Quantization
	0
	-50
(ns)	-1000
	100
Offset
	50
PPS
	0
Corrected
	0
	-50
	-100

Figure 5-2

100	200	300	400	500
	Time (seconds)

100	200	300	400	500
	Time (seconds)

100	200	300	400	500
	Time (seconds)

Removing the Quantization Error from the PPS Output

5-8 Acutime 2000 Synchronization Kit User Guide