지적측량을 위한 Network RTK-GPS의 적용에 관한 연구

지적측량에 Network RTK-GPS를 적용하는 방안을 연구했다.

The types of Network RTK which have been developed so far are of two types VRS(Virtual Reference Station) method of the Trimble company of Germany, and GNSMART/GEO++ jointly developed by GEO++ and Leica of Germany which is an intial model, and now there is a MAC method of Spider Net which was independently complemented and developed based on the initial version. In this study, a network of MAC type was constructed in the Gyeonggi-do area to analyze the usefulness and validity of the Network RTK-GPS.

6 sites were selected to conduct GPS observation for 24 hours, and the impact of multipath resulting from the changes in the sky visibility and satellite elevation angle and signal-to-moise ratio was analyzed. By determining the ITRF of each site, coordinates were determined in connection with IGS network. Then, 21 check points were established in Gimpo area of Gyeonggi-do, and static survey was performed at 4-hour interval and for each check point, observation has been done at least in 7 times of Network RTK survey at 20 seconds of retrieval intervals.

The result showed high accuracy in the difference between the coordinates determined immediately by the in-field network survey and the current performance was 1-2cm. Through the results obtained by this study, the merits of the Network RTK method over a single RTK method were identified. Its biggest benefit is the expanded range of survey and efficiency of practice. Particulary, within the range where a network is established, if an existing control point is lost, it is possible to recover it accurately on the spot; and it was proven by this experiment that, in case of a newly established point, it is possible to set up one immediately on/at the desired place and time immediately.

In summary, it is proved that a network survey has the accuracy, scalability and efficiency and it is expected that the network survey will contribute to the cadastral survey. This study proposed the necessity for establishment of a nationally integrated network.