The Resarch Of Precision Optimization Based On GPS Positioning With Code Pseudorange

Global Positioning System (GPS) is a new generation of sophisticated satellite navigation and positioning system. GPS is global, round-the-clock, continuous real-time three-dimensional navigation and positioning capabilities, a wide range of value and development potential, including three-dimensional observation points GPS positioning has been an important area of research and application.GPS data processing quality's good or bad directly affect the accuracy of GPS positioning.Based on data processing and computer application technology, focusing on the output NMEA0183 GPS static positioning data processing were studied, analyzed and summarized in the domestic and international experience in the GPS data processing and data processing on the basis of research results, research and the single point of the three-dimensional positioning GPS data processing data content. The article first introduced the GPS system composition and work principles, a detailed account of the general and wider use of GPS handset existing problems, as well as the C/A code NMEA0183 GPS handset output format and content. Against ordinary C/A code GPS handheld 3D point positioning accuracy issues analysis, the average error over time increase the distribution of, and to put a 3-D single-point positioning accuracy optimization method, Design and Implementation of the Data Processing NMEA-0183 system.The results show that: (1)The smallest DOP method's positioning accuracy is superior to simple average method, the smallest Euclid distance sum method at the same time, the level of accuracy for the calculation is 1.69m, Altitude height accuracy is 2.00 m. After precision optimized, C / A code GPS handhelds static positioning accuracy can reach the highest level of accuracy of 1m, and the vertical accuracy is within 2m.(2) Using system error correction can substantially improve the static single point positioning accuracy, the level of accuracy can achieve within 2m.(3) GPS plot cloud lever time array's average error appeared after continued two hours observation,the error curve tends to straight, that error close to system error.