The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Voi. XXXVII. Part B4. Beijing 2008
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Figure 5. The chosen vine-parcels in the province of Lemesos
After the analysis and the processing of the measurements, with
the use of algorithms and appropriate software programs and
the help of the RTCM protocol, the final values of the
coordinates of the boundary points are derived. Figures 6,7 and
8 show the boundaries of the three chosen parcels as they are
defined from the cadastral records (white color) and from the
GPS measurements (red color). The improvement of their
boundaries positional determination is obvious and can reach a
few decades of meters. Figure 9 gives the range of the
corrections of the boundaries positions. With the application of
the kinematic positional determination, in real time, the
accuracies achieved are better than 1 m.
Figure 6. Boundaries of vine-parcel 1
Figure 7. Boundaries of vine-parcel 2
Figure 8. Boundaries of vine-parcel 3
Figure 9. The range of the correction values of the boundaries
positions of the parcels
3.2.4 Case 4: Aerial Photography Combined with
GPS/INS data
During an aerial photography campaign, the PSI network was
used in conjunction to GPS/INS data of the aircraft, the purpose
being the determination of the flight line (Fig. 10.). Double
frequency GPS receivers aboard the aircraft were used and the
technique of relative kinematic positioning determination was
applied (on-the-fly solution of phase ambiguities). The GPS
stations of the PSI network were used as referenced receivers.
The final coordinates of the photo centers as well as the
orientation angles were determined. The positional accuracy
was evaluated with the use of data from permanent GPS
stations. The achieved results of better than 10cm in position
and 20 cc in angles are acceptable at least as good
approximations, and depending on the final map scale, as final
results as well.
Figure 10. Determination of flight trajectory for direct geo-
referencing of aerial photography
4. CONCLUSIONS-DISCUSSION
This paper introduced a new permanent GPS network
installation study and describes basic test cases used for
location and mapping services.
The achieved results (Table 2) show that the positioning
precision level obtained for differential GPS, phase fix solutions,
RTK and single point positioning is actually more optimistic
than expected (based on the effectiveness of each method and
the used hardware).