Development of RTK-GPS Field Quality Checking Module for Korean Cadastral Resurvey Project

SUMMARY Real-Time Kinematic Surveying (RTK-GPS) provides the surveying results in the field, but there is a no reliable way to verify the reliability of surveying results obtained by RTK-GPS. Therefore, cadastral surveyors can not make best use of RTK-GPS in cadastral surveying that demands high accuracy level. If surveying data has some mistake or error in RTK-GPS surveying, we have to resurvey to check the distance between RTK-GPS and Total Station (TS) at the same field. The purpose of this study is to verify the quality of RTK surveying results by NMEA data obtained by RTK-GPS and to develop a method in order to enhance the reliability of cadastral surveying so that it could be applied to field surveying. For this, the module which can verify the quality of RTK-GPS surveying results in the field was developed. In the testing module, $GPLLQ data suppling location information can be identified during surveying operation through the PDA screen and RTK-GPS data could be received with the permitting the accuracy and the number already set, calculating standard declination and storing average measurements as decisive coordinates. In order to evaluate the efficiency of the verification module, the results of pilot surveying by TS surveying were compared and analysed. As a result, it is illustrated that the quality verification module of RTK-GPS surveying results could be applied to cadastral surveying very usefully.