GNSS Multi-Constellation Autonomous Integrity Monitoring And Signal Quality Evaluation Technology Research

With the rapid development of satellite navigation technology, it applicates not only in the military field such as sea, land, air and outspace, but also in the civilian areas such as aviation, transportation, agriculture and building.With the constant improvement of the precision, the integrity requirements of the navigation system are also more and more strict. The author of this paper has conducted a series of research; the concrete aspects of the research organized as follows:The first part is focused on receiver integrity autonomous monitoring in case of multiple failures. The traditional fault detection and identification approaches assumes only one faulty measurement, this assumption is no longer valid if the number of satellite signals increases as expected with inclusion of the new satellite systems. It is highlighted that present RAIM techniques have limitations because of a low recognition rate for multiple fault. This paper presents an integrity monitoring technique by using parity space vector subspaces generated by any two columns of the matrix; by parity vector under judgment no noise in the feature space projection correlation to identify the failed satellite. Meanwhile, by analyzing the two fault vector direction and failure deviation of amplitude, binaries are given user error protection level calculation method of fault conditions. Finally, under a dual system based on feature space for double fault identification algorithm for simulation analysis, the simulation results show that, compared with the RAIM algorithm based on recognition threshold, the proposed algorithm for fault detection rate raised from 60% to 90%.The second part of the study aims at evaluating the performance of Advanced Receiver Autonomous Integrity Monitoring(ARAIM). The total allowable Pr{HMI} and false alert probability requirement is equally divided among the faults of all N satellites in view, likewise the existing RAIM algorithm for integrity risk dynamic distribution calculation of complicated problems, given initial conditions reduce the number of iterations to be suboptimal solution, dynamic allocation scheme improves the probability of dangerous misinformation. Compared with the average integrity risk allocation algorithms, improved algorithms can effectively reduce the level of protection and improve system availability while reducing the integrity of computational complexity theory of risk optimal allocation algorithm. Finally, ARAIM algorithm under different application availability through simulation analysis, simulation results show that the ARAIM algorithm under multi-constellation can effectively improve the integrity of the performance, using Bei Dou with GPS improves availably of ARAIM and its integrity performance, and can be able to meet the requirements of China regional LPV-200.The third part makes a design and implementation for GNSS offline signals monitoring with unknown parameters, cannot take advantage of capturing and tracking estimation of signal parameters for signal monitoring and evaluation background, combined with practical needs, using moving correlation and data accumulation method for navigation signal parameter estimation based on narrow-beam antenna. Based on autocorrelation characteristics of navigation signals through a small slice of the data associated with the original signals estimation of GNSS signal code cycle, set parameters such as boduopule, by cycle accumulation averaging improves signal to noise ratio, further estimates signal parameters such as signal carrier phase, initial code phase, using simulations to validate the effectiveness of the method. Finally, example offline signal quality assessment results for the various parameters and for the different signal are monitoring and assessment in orbit, build a navigation signal quality monitoring and analysis of hardware and software platforms, and realized an analysis of GNSS signal assessment.At last, the research work of this dissertation and its application are summarized, and noted that deficiencies still exist in the present research work and improvement is part of the future. Integrity of the content of this paper on satellite navigation system is of great significance, its research results can be applied directly to the in-orbit satellite navigation signal quality monitoring and evaluation.