Beidou plus GPS dual-pattern single point positioning method

Abstract

The invention discloses a Beidou plus GPS dual-pattern single point positioning method. The method is characterized by comprising the following steps of 1, obtaining observation data and navigation data of each epoch; 2, extracting pseudo-range measurement values, time information and ephemeris parameters; 3, determining the position (Xs, Ys, Zs) of each satellite in a WGS-84 earth centered earthfixed coordinate system; 4, obtaining the distance between each satellite and the earth; 5, obtaining measurement error variances sigma2 of the pseudo-range measurement values and conducting weightingon the pseudo-range measurement values; 6, obtaining a pseudo-range residual error y and a coefficient matrix H of an observation equation y=H delta x+v; 7, obtaining the position of a receiving machine and satellite elevation angles which are figured out by means of k-th iteration; 8, judging whether or not an iteration end condition is satisfied and deciding whether or not the iteration processcan be continued. The method has the advantages of being high in operability, convenient to use and accurate in positioning; by means of the method, the horizontal precision for positioning can reach2 meters, and the vertical precision for positioning can reach 3 meters.

Description

technical field [0001] The invention belongs to the technical field of satellite navigation and positioning, in particular to a Beidou+GPS dual-mode single-point positioning method. Background technique [0002] At present, both the GPS signal and the Beidou signal have basically completely covered the mainland of China, and it is very common to use GPS or Beidou satellite navigation system for navigation and positioning. In some occasions, such as urban rescue, field rescue, driving navigation and other application scenarios, it does not require particularly high positioning accuracy, and requires low equipment cost and low equipment complexity, which can be satisfied by using pseudo-range single-point positioning. Such demand. However, since single-point positioning requires at least four satellites with good observation conditions, whether it is a separate GPS system or a separate Beidou system, there are insufficient effective satellites in many occasions, resulting in ...

AI Technical Summary

Problems solved by technology

However, since single-point positioning requires at least four satellites with good observation conditions, whether it is a separate GPS system or a separate Beidou system, there are insufficient effective satellites in many occasions, resulting in a greatly reduced accuracy of single-point positioning or even inability to locate The adverse effects of high-rise buildings, tree shade and other occasions with more multi-path propagation. Moreover, in single-system positioning, due to less redundant information, the positioning trajectory fluctuates greatly and is unstable.

Some of the current popular single-point positioning methods need to check the position information of the receiver first, which has relatively large limitations; some use the least square method to directly solve the solution, and the solution accuracy is very poor; some do not consider the accuracy of the pseudorange measurement value, directly Let the obtained measurement values ​​participate in the solution, and there is still room for improvement in accuracy

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