Adaptive user autonomous integrity monitoring method

Abstract

The present invention provides an adaptive user autonomous integrity monitoring method. The method comprises: converting the system time of different navigation systems into the same as that of the main system; converting the reference coordinates of different navigation systems to be consistent with the main coordinates; respectively estimating a satellite clock difference, a troposphere delay, an ionosphere delay, and a multipath delay; obtaining a PDOP (position dilution of precision ) value through observation data and satellite ephemeris data; when PDOP<3, using the positioning domain-based location solving method; when 3<PDOP<6, using the measurement domain-based location solving method; when 6<PDOP, determining that the system is not available; using the parity vector method for fault detection; and using the maximum likelihood estimation for fault identification. According to the method provided by the present invention, the exploitation and utilization of observation information can be maximized, and the influence of the gross error on the positioning result can be reduced, so that the performance of the autonomous integrity monitoring of a receiver can be enhanced.

Description

technical field [0001] The invention relates to a satellite navigation integrity monitoring method. Background technique [0002] Integrity is one of the four major indicators of GNSS (Global Navigation Satellite System). It is a measure of the confidence in the correctness of the information provided by the navigation system, including the ability of the system to issue an alert to the user when it cannot be used for navigation. Unhealthy satellites, failure to issue warnings in a timely manner, and intentional / unintentional interference can seriously affect satellite navigation services and integrity services. Reliable integrity services are achieved through integrity monitoring. The main function of integrity monitoring is to effectively detect and eliminate the faults that affect the positioning accuracy of the system. [0003] At present, the development of satellite navigation integrity technology mainly starts from the satellite navigation precision approach technol...

AI Technical Summary

Problems solved by technology

However, there are some limitations in the ground-based augmentation system: (1) the cost is high

Due to the need for synchronous satellites and a large number of ground monitoring stations, the system structure is complex and the operation and maintenance consumption is huge

For ordinary users, the system cost is unaffordable

(2) The service area is limited

The ground-based augmentation system is significantly limited by distance. Studies have shown that the performance of ground-based augmentation will be weakened if the distance exceeds 10 kilometers, which is not conducive to the needs of users with strong mobility.

(3) High environmental requirements

For users in multi-block environments such as cities with high-rise buildings, woods, and mountains and valleys, such an observation environment cannot meet the requirements for receiving ground-based enhanced signals

In addition, for a multi-occlusion environment, the signal resources that the user receiver can receive are scarce and limited, and there is no guarantee that continuous navigation signals can be obtained

(4) Poor alarm timeliness

[0018] Therefore, for complex environments, the problems that the user end may encounter are: on the one hand, the observation environment of civilian receivers is changeable

[0024] However, participating in the positioning solution based on the clock error prediction value will introduce a new error source, that is, the clock error prediction error. When the user can see enough satellites, this error will not improve the positioning result, but may exacerbate the uncertainty of the positioning result , thus affecting the performance of fault detection and fault identification

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