Performance of Stand-Alone GPS - Understanding GPS: Principles and Applications - page 374

Calendar year 2003

10

9

8

7

6

5

Average daily global performance:
5.4 ns (95%)

4

3

Average worst site performance:
6.4 ns (95%)

2

1

0

January-03 April-03 July-03 October-03 January-04

Date calendar year 2003

95% time transfer user error --
global median
95% time transfer user error --
worst site

ANALYSIS NOTES

- All-in-view PPS dual-frequency time
transfer receiver with five-degree mask
- 4 ns RMS error in knowledge of bias
between GPS time and USNO UTC
- 80 cm (1 ) receiver thermal noise
- One minute samples over 24 hours,
2

σ

2 degree equally spaced global grid ×

Figure 7.36 Global trend in static GPS time transfer receiver performance [relative to UTC

(USNO)].