Dr. M. Sc. Gintcho Kostov, Bulgaria: "Geo Zemia" LTD
Dr. M. Sc. Gintcho Kostov, Bulgaria: "Geo Zemia" LTD
Dr. M. Sc. Gintcho Kostov, Bulgaria: "Geo Zemia" LTD
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
1. Introduction
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
2. Aims of the study
the influence of the disturber onto the results from the measurements in RTK mode
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
3. Conducted Geodetic Measurements. Study and Specifics of the Behaviour of the Rover
-the reference GNSS station - set up in close proximity to the area under study; -RTK measurements were conducted inside the disturbed region; -the lengths of the measured spatial chords were less than 1 km.
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
3. Conducted Geodetic Measurements. Study and Specifics of the Behaviour of the Rover
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
4. Used Criteria for Assessment of the Overall Quality of the Measured points
In this study the following quality criteria were applied: 1. Diagonal elements of the co-variance matrix: Q11, Q22 and Q33; 2. Position quality - Mp; 3. Height quality - Mh; 4. Position and height quality - M3D;
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
5. Results and Analysis from the Measurements in RTK mode
point N 335 336 350 351 352 353 significant difference in the quality 354
355
Mp [mm] 6 6 5 5 5 6 7
5
Mh [mm] 11 11 10 10 10 11 17
10
M3D [mm] 12 12 11 11 11 12 18
11
370 371
0.00001918 0.00001535
0.00001320 0.00001268
0.00010867 0.00010175
5 5
10 10
11 12
0.63 0.64
Table 1. Values of the criteria and results for the overall quality assessment
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
5. Results and Analysis from the Measurements in RTK mode
Q11
0.00001155 0.00001558 0.00001143 0.00001443 0.00001176 0.00001133 0.00001439 0.00001137 0.00000432 0.00001135 0.00001174 0.00001173 0.00001196 0.00001195 0.00001197 0.00001185
Q22
0.00001037 0.00001339 0.00001036 0.00001110 0.00001111 0.00001036 0.00001105 0.00001119 0.00000408 0.00001070 0.00001180 0.00001129 0.00001178 0.00001119 0.00001170 0.00001119
Q33
0.00009547 0.00020323 0.00009719 0.00012543 0.00012155 0.00010028 0.00011995 0.00011799 0.00004336 0.00010613 0.00014581 0.00013052 0.00015797 0.00013835 0.00015670 0.00013371
Mp
6 6 4 6 5 4 4 5 10 5 5 5 5 6 6 6
Mh
12 16 9 13 13 9 9 11 22 11 13 12 12 16 15 15
M3D
13 17 10 15 14 10 10 12 24 12 14 13 13 17 16 16
rating
0.66 0.55 0.69 0.63 0.68 0.70 0.65 0.69 0.56 0.69 0.68 0.68 0.68 0.55 0.58 0.58
low quality
Table 1. Values of the criteria and results for the overall quality assessment - continued
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
5. Results and Analysis from the Measurements in RTK mode
point N
419 420
Q11
0.00001679 0.00001245 0.00001246 0.00001254
Q22
0.00001275 0.00001099 0.00001099 0.00001099
Q33
0.00012999 0.00011075 0.00011050 0.00010936
Mp
8 6 6 5
Mh
16 13 12 11
M3D
18 14 14 12
rating
0.45 0.65 0.66 0.67
421 422
low quality
425 426
0.00001308 0.00001312
0.00001164 0.00001165
0.00012041 0.00011957
8 7
17 15
18 16
0.47 0.54
434 435
0.00001316 0.00001331
0.00001102 0.00001104
0.00009676 0.00009961
5 5
10 9
11 10
0.67 0.67
5 6 6 6 6 6 7 6
10 13 12 12 13 13 14 13
11 14 13 14 14 14 15 14
Table 1. Values of the criteria and results for the overall quality assessment - last
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
6. Analysis of the Results
According to the calculated results, it could be summarized: 1. variations in the accuracy were ascertained; 2. a degradation of the accuracy up to 24 mm in the open field was observed; 3. M3D quality criterion was not sufficient for complete control of the accuracy for points NN 397 and 398. More criteria should be considered and used. It must be noted that several years ago in the region under study GNSS measurements could not be conducted due to the strong influence of the active disturber.
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
7. Conclusions
Based on: - continuous improvement of the system; - considering the accuracy results, Geodetic measurements conducted with GNSS equipment nowadays are characterised with better overall quality and reliability in comparison with the passed last years. Taking in mind the quality assessment, the current status of the system and GNSS modernizations it could be concluded: - Currently enough operational satellites exist, which can be used for geodetic determinations and be delivered good quality results in a region with operating active disturber. - The future efforts for GNSS improvements are highly encouraged in order to be obtained: better reliability in the determinations and higher overall quality of the results within places with operating active disturber.
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
REFERENCES:
Kostov, G. Assessing of the Overall Quality of GNSS Determinations, Using Specific Values of Parameters. Third International Conference on Cartography and GIS. June, 15-20, Nessebar, Bulgaria, 2010. Minchev, M., Iv. Zdravcev, Iv. Georgiev, Foundations of the application of GPS in geodesy, Sofia UACEG, 2005 (in Bulgarian). Ministry of Regional Development and Public Works. Issued DV issue 79/11.10.2011. Instruction N RD02-20-25/20.09.2011 for determination of geodetic points, using GNSS. In effect from 11.10.2011. (in Bulgarian). Tiwari R., Soumi Bhattacharyaa, P.K. Purohitb, and A.K. Gwala. Effect of TEC Variation on GPS Precise Point at Low Latitude. The Open Atmospheric Science Journal, 2009. Tiwari S., Amit Jain, Shivalika Sarkar, Sudhir Jain and A K Gwal. Ionospheric irregularities at Antarctic using GPS measurements. J. Earth Syst. Sci. 121, No. 2, Indian Academy of Sciences, April 2012. Wellenhof, B., Herbert Lichtenegger, James Collins, GPS Theory and practice, Springer-Verlag/Wien, Austria, 2002. (in Bulgarian).
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
WEB: http://en.wikipedia.org/wiki/GLONASS http://en.wikipedia.org/wiki/GPS_modernization http://waas.stanford.edu/~wwu/papers/gps/PDF/IWG/sbas_iono_scintillations_white_paper.pdf http://www.ion.org/search/view_abstract.cfm?jp=p&idno=1292
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Study of the Behaviour of the Rover and Assessment of the Overall Quality of the Results from RTK Measurements, Conducted in open-Field - Influenced by Active Disturber
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