Method for monitoring completeness of ground based augmentation system (GBAS)

Abstract

The invention provides a method for monitoring the completeness of a ground based augmentation system (GBAS). The method comprises the following steps of: carrying out real-time normalization processing on the carrier to noise ratio of a received satellite navigation signal to obtain a normalized carrier to noise ratio; carrying out real-time time accumulation on the normalized carrier to noise ratio to obtain a carrier to noise ratio accumulated summation of current time; calculating to obtain a current value of a monitoring threshold value according to the noise ratio accumulated summation of current time through a markoff chain; and comparing the noise ratio accumulated summation of current time with the current value, and if the noise ratio accumulated summation exceeds the current value, sending out alarm information. In the invention, a mathematical statistic method of deviation error accumulation is adopted to monitor the carrier to noise ratio of the satellite navigation signal in real time in a process of processing monitoring data of the GBAS carrier to noise ratio completeness, thereby simplifying the calculated amount, realizing the real-time update of the threshold value and improving the precision of a positioning result.

Description

technical field [0001] The invention relates to a integrity monitoring method of a ground-based augmentation system, which belongs to the technical field of satellite navigation. Background technique [0002] The positioning principle of the Global Navigation Satellite System (GNSS for short) is: the user calculates the distance from the user's receiver to the satellite and the real-time position of the satellite according to the satellite navigation signal received from the navigation satellite. When the distance of four satellites is reached, the real-time three-dimensional position of the user can be calculated. However, the distance measured by the user from the satellite to the user's receiver actually includes errors caused by the satellite's ephemeris, star clock, ionosphere and tropospheric delay, receiver thermal noise and multipath effects, etc., so the measured The distances are actually pseudoranges. For example, for a Global Positioning System (Global Position...

AI Technical Summary

Problems solved by technology

However, when the existing GBAS is used for integrity monitoring, different thresholds need to be calculated according to the current terrain, the position of the receiver and the position of the satellite, and a large amount of data statistics are required, and the calculation is very complicated; and the calculated thresholds cannot be real-time Update, so the latest environmental changes cannot be reflected in time, thus affecting the accuracy of positioning results

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