Algorithm Research And Implementation Of GPS Network Adjustment For Petroleum Geophysical Exploration Surveying

Adjustment of GPS(Global Positioning System)network is used to evaluate the accuracy of GPS network,find and eliminate the gross errors in observations of GPS baseline vector that may exist in the network and get the coordinates,and occupies an important position in the GPS measurement data processing.In this paper,combined with the characteristics of oil geophysical prospecting,conducts the research to the processing flow and algorithm of GPS network adjustment,and programming implementation,has a certain value.This paper introduces the GPS data processing in the measurement of common coordinate system and basic principle of coordinate transformation;on the GPS baseline solution methods are studied,including: traditional baseline solution of double difference location method based on precise point positioning based on the(precise point positioning,PPP)of the baseline method;research network adjustment theory and related algorithms of GPS engineering control,three dimensional unconstrained adjustment,three dimensional constraint adjustment and two-dimensional constraint GPS net adjustment;introduces several basic methods of GPS height fitting.Through the use of MATLAB language,this paper realizes the adjustment of GPS control algorithm,and the corresponding program is compiled by CPI GPS;control network and data network Jilantai area measurement of petroleum exploration GPS control as an example,with the COSAGPS software and TGO software processing results of the comparison and analysis of self GPS network adjustment program to verify the algorithm,draw the following conclusions: 1)Self GPS network adjustment program of three dimensional unconstrained flat difference result of the maximum error in the three coordinates are less than 1.0cm,the system error is better than that of 7mm,the root mean square error(RMS)is better than that of 7mm.2)The program of 3D constrained adjustment of the maximum error in the three coordinates are less than 1.5cm,the system error is better than that of 8mm,the root mean square error(RMS)is better than that of 8.5mm.3)The maximum error by the program of plane coordinates of the two-dimensional constraint adjustment within 2.2cm.The system error is about 1cm,the root mean square error(RMS)is about 1cm.4)The maximum error of the results of the program height fitting is about 4.5cm,the deviation of the system is about 2cm,and the root mean square difference(RMS)is about 3cm.The statistical data to verify the rationality of self correctness and program design of GPS network adjustment program algorithm,the commercial TGO software processing results and measurement of petroleum exploration in the widely used are basically the same,can meet the actual production requirements.