Research On Attitude Determination Algorithm Based On GPS Single Antenna

With the rapid development of satellite navigation technology,the application scenarios of attitude determination become increasingly wide.Reducing cost,improving stability and simplifying structure are becoming the current research trends.Attitude information provides more detailed motion state information,and it plays an irreplaceable role in high-tech aspects of unmanned technology,micro-robot and drone.It is hard for GPS antenna configuration to adopt multiple antennas,thus it is limited in some scenarios.At the same time,there are problems in the multi-antenna attitude determination technology,such as difficulty in antenna installation and deformation between antennas.Researching and designing a method of GPS single attitude determination can simplify the device complexity,reduce the antenna size,reduce measurement costs,and effectively expand the scope of the application of attitude determination.This thesis focuses on the observation model of GPS single antenna and the elimination of errors.Based on this,the single antenna attitude determination.Model is deduced and the process of solving the attitude angle is discussed.Firstly,a GPS single antenna attitude determination model is established.In the process of designing GPS single antenna attitude determination algorithm,in order to ensure the accuracy of attitude determination,a key problem to be solved is to improve the relative positioning accuracy at different moments.The reasons for the errors in the observation model are analyzed.Combined with the single-difference and double-difference observation models,the double difference method can effectively eliminate most of the common errors in satellites and receivers.After the linearization,a single-antenna attitude determination algorithm model based on time series is deduced.Secondly,the process of solving the attitude angle is discussed.The direct method and the least squares method are respectively used to solve the attitude angles.By comparing and analyzing the two solving algorithms,the attitude accuracy obtained by the least squares method is higher.In order to further improve the accuracy of the attitude determination system,the random error in the attitude determination process is analyzed,an error model is established,and the elimination method is given.Finally,simulation of each algorithm module in the single antenna attitude determination scheme is implemented.In order to further improve the accuracy of theattitude solution,based on the least squares orthogonal decomposition theory,the LAMBDA algorithm is given for ambiguity search.By building a hardware test platform to collect GPS raw observation data,the above data is analyzed and tested,and the accuracy,stability,and feasibility of the single antenna attitude determination system scheme are verified.The experimental results show that the GPS single-antenna attitude measurement scheme designed in this thesis can effectively provide a stable attitude angle and expand the application scope of attitude determination.