Research And Realization Of Direction Determination Based On Global Satellite Navigation System

As the growing maturity and improvement of satellite navigation receiver’s technology, the application of this technology has been broadened into some brand-new fields. One of the new application is real-time direction determination, namely attitude angle of motion vehicle by taking full use of several antennal or receivers, which leads to greater demands on respect of measurement accuracy and related algorithm.To meet the demands of higher measurement precision, the direction determination has to involve differential positioning technology and take carrier phase from satellite signal as observation because it is more precise than pseudo range. And to meet the demands of better algorithm as well, the direction determination must be capable of rapidly solving ambiguity of carrier phase at any time. Specifically, in order to construct accurate equations about double differential, it requires the well-functioned receivers to keep trace of adequate satellites with high elevation steadily and measure exact coordinate of location and satellites as well as carrier phase from these satellites. Then, solving ambiguity by least-square ambiguity decorrelation adjustment method, which is also called LAMBDA, and calculating real-time relative positioning by weighed least square method. Meanwhile, checking out whether cycle slip happens can guarantee the ambiguity solved correctly.This article studies principle and method of differential positioning theoretically, and explains its feasibility and discusses the effects from all kinds of error. In addition, the hardware platform is designed and built with two DL-V3receivers and these corollary equipment produced by NovAtel. The hardware platform could offer related data of GPS signal, with which the attitude angle of motion vehicle would be computed by programming in MATLAB. At last, the outcome would be confirmed and the characteristics of differential positioning would be analyzed further.The experiments of this topic indicate that double-differential positioning based on carrier phase of the baseline is capable to compute the direction of corresponding motion vehicle if the baseline, consist of two well-functioned receivers, steadily locks enough common satellites with high elevation.