Application Research Of BeiDou Triple Frequency On BDS/GPS Dual Frequency Differential Beacon

RBN-DGNSS was a new technology to solve the problem of surface positioning,but most of the beacon built in the coastal area,provided auxiliary positioning for ocean.In order to solve the problem of underwater positioning in river vessels,in 2014 Southeast University and the CHANGJIANG WATERWAY BUREAU established a Beidou/GPS dual-mode dual frequency differential beacon,the signal could cover Jiujiang to Nanjing,and provide the plane positioning about meter level,this beacon could satisfy the Yangtze River Navigation demand.But the beacon could only sent dual frequency signal,this paper studies how to use the triple frequency data to provide higher positioning accuracy,could promote the research and application value for the beacon,and extend the positioning method of Beidou system.This paper presented a new triple frequency data positioning combination model of super wide lane and wide lane,and verify the method with experimental data.The main contents and conclusions of this paper are as follows:(1)Based on the application of Beidou System on the BDS/GPS Dual Frequency Differential Beacon,expounded the principle of beacon differential positioning,and analyzed the advantage of Beidou multi frequency data.Systematically expounded the basic theory of the Beidou system positioning.Especially include the development of the Beidou system,the constellation structure,signal characteristics,coordinate system and time system after Beidou three generation satellite using.Studied positioning method of the triple frequency data,introduced its application in differential position.Secondly,systematically discussed system,structure and function,the characteristics of innovation of the BDS/GPS Dual Frequency Differential Beacon,described the operation process of the beacon differential positioning system.(2)Analyzed the application of Beidou system differential positioning model in beacon positioning,and studied the single frequency and dual frequency phase combination model to enhance the positioning accuracy.Based on the introduction of the Beidou system positioning model,analyzed the error generated in the positioning model and introduced partial correction model of the error;studied difference positioning model,and analyzed the theory of improving the positioning accuracy using carrier phase smoothing pseudorange correction data.Based on the application of dual frequency data,studied dual combined positioning model(wide lane combination,ionosphere free combination and MW combination),and analyzed the positioning model,combination of wavelength,positioning accuracy,error of different combination observation.Compared single frequency phase smoothing pseudo positioning result to dual frequency ionosphere free combination positioning result using two groups' data(8cm and 164.5km).The results showed that the plane precision of the dual frequency ionosphere combination is 1.3cm in the zero baseline(8cm),and the plane precision of the single frequency ionosphere combination is 2.8cm,two results are similar because of the similar distance of two stations.The plane precision of the dual frequency ionosphere combination is 0.905m in the zero baseline(8cm),and the plane precision of the single frequency ionosphere combination is 1.029m,the result showed the precision of dual frequency positioning was better than that of single frequency in long distance.(3)With the beacon differential positioning system,this paper proposed a kind of differential positioning method using ultra-wide lane and wide lane combination phase observation data of triple frequency data.Solved the ambiguity using ultra-wide lane and wide lane combination phase observation data in the base station,and retained two decimal deviations in the calculation process.Using the accurate coordinates of the base station,Combined the observed values fixed ambiguity according to the ionospheres' model.And calculated the overall deviation.Sent the total deviation of the ionospheres' combination and two decimal deviation parts to the user station;fixed the ambiguity of ultra-wide lane and wide lane combination phase observation data using two decimal deviation.Corrected the ionospheres' combination observation data using the total deviation from the base station,and position the user station coordinates.Selected two sets of data to verify the accuracy of the positioning model.Computed the positioning results using short distance data(8cm),ultra-wide lane combination positioning plane accuracy is 1.2cm,dual frequency ionospheres' combination positioning plane accuracy is 1.3cm.The ultra-wide lane combination elevation positioning accuracy is 0.5cm,which is better than the dual frequency ionospheres' combination elevation positioning accuracy which is 2.7cm.The accuracy of plane positioning is improved by 2.0%,and the accuracy of elevation positioning is increased by 80.0%.Computed the positioning results using long distance data(164.5km),ultra-wide lane combination positioning plane accuracy is 39.1cm,dual frequency ionospheres combination positioning plane accuracy is 90.5cm.The ultra-wide lane combination elevation positioning accuracy is 64.67cm,which is better than the dual frequency ionospheres'combination elevation positioning accuracy which is 82.47cm.The accuracy of plane positioning is improved by 56.0%,and the accuracy of elevation positioning is increased by 21.0%.The experimental results showed that the long distance differential positioning using the ultra-wide lane and the wide lane combination can improve the positioning accuracy.