ASSESMENT OF REAL TIME KINAMATIC GPS POSITIONING ACCURACY USING INTERNET WITH DIFFERENT PROTOCOLS

The research paper presents a prototype system to accuracte, efficient and costeffective GPS positioning using real time kinematic RTK mode, with RTCM correction message. An experiment was implemented and tested by applying TCP/COM socket function using stream the RTCM correction wirelessly. In this approach, two tests were conducted by applying internet protocols TCP, UDP. The first test was a static, the second test was conducted while the receiver was moving. The result of the first test showed a horizontal precision of about 4 cm and a vertical precision of about 6 cm at 98% level using TCP and 2.7cm, 5.8 cm at 98% level for horizontal and vertical precision respectively using UDP protocol. The second driving test showed promising results with low latency, high accuracy, as the results showed that the maximum real-time positioning errors, using RTK technique, were less than 15cm for easting coordinates and less than 12cm for northing coordinates. Finally, it was concluded that: 1-Transmitting survey data and corrections in RTCM format over the internet could be the standard for future solutions in providing necessary information for RTK applications as it is more efficient than conventional RTK. 2- Transmitting the surveying data using mobile wireless depends on size. 3- UDP internet protocol is recommended for real-time GPS.