SIMT(NIST) versus SIMT(LNM) via Common-View GPS
1 Day Averages 1 Hour Averages 10 Minute Averages Next Date Last Date Flip    

Laboratory 1National Institute of Standards and TechnologyID Number006End Date2021-04-24
Latitude 39° 59 min 44.579 s NCounter Delay 0.23 nsReference SourceSIMT(NIST)
Longitude105° 15 min 43.185 s WREF Delay 433.4 nsMask Angle10°
Altitude1646.72 mReceiver Delay-5.4 nsReceiver Temp.28 °C
Laboratory 2Centro Nacional de Metrologia de GuatemalaID Number015Baseline3128.137 km
Latitude 14° 35 min 24.774 s NCounter Delay -0.16 nsReference SourceSIMT(LNM)
Longitude 90° 32 min 31.394 s WREF Delay 0 nsMask Angle10°
Altitude1509.00 mReceiver Delay168.3 nsReceiver Temp.26 °C

Hours in
Common-View		 Mean Time
Offset (ns)		 Range (ns) Frequency Offset Confidence (r)
24 -39.26 12.26 +6.30 x 10-14 +0.42




Allan Deviation
Averaging Period ()
(hours, minutes)		 Samples Frequency
Stability
0 h, 10 min 142 4.00 x 10-12
0 h, 20 min 140 2.68 x 10-12
0 h, 40 min 136 1.44 x 10-12
1 h, 20 min 128 7.33 x 10-13
2 h, 40 min 112 3.85 x 10-13
5 h, 20 min 80 2.79 x 10-13


Time Deviation
Averaging Period ()
(hours, minutes)		 Samples Time
Stability (ns)
0 h, 10 min 142 1.39
0 h, 20 min 139 1.44
0 h, 40 min 133 1.19
1 h, 20 min 121 0.97
2 h, 40 min 97 1.53
5 h, 20 min 49 2.89


SIMT(NIST) - SIMT(LNM)
(common-view tracks from individual GPS satellites)
GPS
PRN		 Minutes
(In-View)		 Minutes
(Common-View)		 Range (ns) Time
Deviation		 Frequency Offset Confidence (r) View
Detail
1 410 210 17.78 2.19 +3.21 x 10-13 +0.75 View
2 350 300 21.47 2.16 -6.38 x 10-14 -0.46 View
3 370 130 12.68 1.93 +1.08 x 10-12 +0.74 View
4 370 230 9.28 1.31 +3.11 x 10-13 +0.53 View
5 310 290 18.85 1.95 -8.04 x 10-14 -0.60 View
6 310 290 20.51 2.18 +7.41 x 10-13 +0.81 View
7 370 230 8.04 1.21 -2.12 x 10-14 -0.04 View
8 330 210 19.25 1.23 +1.19 x 10-12 +0.76 View
9 330 200 8.30 1.67 +3.00 x 10-13 +0.49 View
10 370 340 15.30 2.36 -3.72 x 10-13 -0.62 View
11 --- --- ---------- ------- -------------- ------ ----
12 240 150 12.01 1.77 -1.04 x 10-14 -0.14 View
13 360 180 11.34 2.25 -6.33 x 10-14 -0.43 View
14 360 340 20.70 2.24 -3.65 x 10-13 -0.46 View
15 280 170 10.63 2.21 +2.26 x 10-13 +0.22 View
16 300 240 18.57 2.14 +3.63 x 10-13 +0.40 View
17 350 290 12.63 1.00 +1.94 x 10-13 +0.37 View
18 380 230 13.26 1.40 -1.97 x 10-13 -0.22 View
19 360 330 14.83 1.87 +8.61 x 10-14 +0.18 View
20 390 360 17.71 2.87 -5.29 x 10-14 -0.11 View
21 390 230 20.47 1.89 +3.29 x 10-13 +0.80 View
22 320 180 7.99 1.60 +2.41 x 10-13 +0.43 View
23 350 210 11.82 1.95 -8.81 x 10-14 -0.24 View
24 380 180 11.49 1.23 +9.07 x 10-14 +0.73 View
25 350 180 18.79 2.15 -9.11 x 10-14 -0.40 View
26 340 230 10.93 1.69 +5.47 x 10-13 +0.70 View
27 430 240 18.09 2.19 +2.11 x 10-13 +0.51 View
28 250 110 12.00 2.25 -8.09 x 10-13 -0.68 View
29 350 210 12.71 1.39 -3.97 x 10-13 -0.40 View
30 310 130 8.88 1.49 -1.00 x 10-13 -0.10 View
31 320 310 13.93 2.30 +1.64 x 10-13 +0.27 View
32 300 280 13.87 2.24 +1.10 x 10-13 +0.21 View


Legend
GPS PRNThe unique pseudo random noise (PRN) code (1 to 32) used to identify each satellite. If no satellite is assigned to a given PRN code, then no data are shown.
Minutes
(In-View)		The number of minutes when the satellite was visible at laboratory 1. During this period, the time difference between the satellite clock and the laboratory reference is measured every second, and 10 minute averages are stored. Since data is recorded in 10 minute segments, the values are even multiples of 10 minutes.
Minutes
(Common-View)		The number of minutes when the satellite was visible at both sites involved in the common-view comparison.
RangeThe difference between the maximum and minimum time offset values (nanoseconds).
Time
Deviation		The time deviation (TDEV) of the 10-minute averages (nanoseconds).
Frequency
Offset		The estimated frequency offset of laboratory 1 relative to laboratory 2 based on a common-view observation of the satellite. This estimate is obtained by fitting a least squares line to all of the recorded data.
Confidence
Level (r)		The confidence level of the estimated frequency offset. The confidence level is the correlation coefficient (r) of the least squares line fitted to the data.
View
Track		Clicking on the View link displays a common-view track from the selected satellite. The number of previous days shown equals the number of previous days shown on this page, up to a maximum of 30 days.