XX IMEKO World Congress, 9-14 September 2012, Busan, Republic of Corea

1. GEODETIC CLASS GPS RECEIVER
AS A STANDARD FOR TIME-
CRITICAL APPLICATIONS
Vukan Ogrizovic1
Jadranka Marendic2
Snezana Renovica2
Sinisa Delcev1
Jelena Gucevic1
1
University of Belgrade, Faculty of Civil Engineering,
Department of Geodesy and Geoinformatics, Belgrade, Serbia
2
Directorate of Measures and Precious Metals, Belgrade, Serbia

2. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
The scope

Civil Engineering, Geodesy and Geoinformatics

Geodetic astronomy

Time-keeping

time synchronization

comparing local clock with UTC

GPS, NTP,...

Metrological laboratory for angle and length
calibration (ML160)
2/11

3. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Device under test
 ML160 time standard
 Geodetic class L1/L2 receiver
 part of Serbian CORS network
 1PPS BNC output
3/11

4. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Equipment
No Measuring equipment Remarks
Name Type Manufacturer S/N
1 TIC CNT- Pendulum 914858
90
2 NetRS 6609/ Trimble 914647 Opt 70
021
3 Digital clock CADM Rohde- 99.6014.02
Schwartz
4 Oscillo-
scope
4/11

5. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Experiment set-up
5/11

6. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Phase-time diagram
6/11

7. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Cycle slip resolution

Sudden jump in GPS integrated phase
measurements

Decreases PVT solution

16 cycle slips during 24 hours

No correlation with phase-time outliers
7/11

8. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
AVAR values
8/11

9. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
AVAR from raw GPS data
9/11

10. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Conclusion and remarks

Permanent ms accuracy of time-marks

Convenient for permanent monitoring of
industrial processes

Microsecond accuracy (astrometry, etc.)?

not reliable

could degrade positional accuracy

To discipline GPS with a rubidium clock
10/11

11. XX IMEKO World Congress, 9-14. September 2012, BEXCO, Busan, Republic of Corea
Thank you
Vukan Ogrizovic, vukan@grf.bg.ac.rs
Jadranka Marendic, marendic@dmdm.rs
Snezana Renovica, renovica@dmdm.rs
Sinisa Delcev, delcev@grf.bg.ac.rs
Jelena Gucevic, jgucevic@grf.bg.ac.rs
The work on this paper is supported by the
Ministry of Education and Science of the Republic
of Serbia (Project of technological development
TR-36048)
11/11