Application And Research On GPS Integer Ambiguity In Attitude Determination

Use of carder phase measurements of the carder gesture to the application of GPS measurement is a new area.GPS measurements posture not only low-cost,but can also provide high accuracy to meet the needs of the general carrier.As GPS navigation and positioning itself with the capacity,GPS attitude measurement system can be widely applied in the route navigation,precision landing,and automatic drive. Therefore,GPS attitude measurement has tremendous potential applications,is a new attitude measurement direction of development.Based on the CPU 1.70GHz,memory 256M,for the Windows XP operating system environment,using MATLAB 7.0 software programming,the paper focuse on analysis and simulation to determine the full realization of ambiguity algorithm and GPS attitude measurement algorithm.The main task of this paper included the completion simulation of the whole ambiguity search algorithm and GPS single epoch single-frequency attitude determination algorithm to achieve the design and simulation.In the whole ambiguity search algorithm aspect,the paper investigated LAMBDA and MLAMBDA algorithms,simulated the two algorithms using MATLAB.And analyzed their performance from three aspects:decorrelation processing,running time and success rate.The results showed that in the considerable success rate circumstances, MLAMBDA algorithm decorrelation has better effect,the process of running a shorter time,thereby enhancing the entire determine the efficiency of ambiguity.In GPS attitude determination algorithm aspect,the paper designed one single epoch single-frequency attitude determination algorithm,and applied LAMBDA and MLAMBDA algorithm into it,and simulated the algorithm using MATLAB.Firstly, analyzes the RINEX data exchange formats,reads key data for attitude measurement algorithm with the actual satellite ephemeris data.Secondly,simulates seven satellite locations.Thirdly,using the pseudo-range measurements of C/A code,through the pseudo-range observation and linear differential equations,and iterative calculates the receiver position.Then,on the best constellation choice principle,achieves a high degree angle calculation and satellite GDOP star-election,and simulates the receiver and four satellite locations.In accordance with the main and alcor stars,completes carder phase two-carrier difference equation,and importes LAMBDA algorithm and MLAMBDA algorithm to complete the whole ambiguity solution,and gives running time of each process,which has proved in the former chapter.Finally,completes the baseline vector solution,calculates single epoch attitude angle,and analyzes solution for ten epoch attitude angle's accuracy,which indicates single epoch single-frequency test attitude algorithm has good accuracy.