恶劣环境下提高可用性的卫星导航定位技术研究
发布时间：2018-11-08 14:36
【摘要】：在卫星导航接收机的应用环境中,可用性容易受到各种环境因素的影响,比如高误码环境下电文校验出错纠正能力有限、可见星不足环境下无法按照传统方法定位、弱信号环境下电文无法接收或更新等,都会导致可用性下降。针对上述问题,本文从电文完好性、接收机钟差建模和卫星轨道外推三个方面展开研究,研究了传统处理方法的不足,提出优化设计方法。本文的研究工作从以下三个方面开展:(1)针对传统BCH纠错方法存在只能对1比特误码进行纠正的问题,提出基于轨道限制的参数误码纠正方法。该方法结合电文参数的物理含义,分析参数的限制范围,对误码的比特位进行识别和纠正。仿真结果表明,提出的纠错方法对于部分参数范围有限的电文高位误码情况可以纠正2比特以上的误码,最后以北斗系统星历为例总结了各个电文参数的比特纠错成功率。(2)传统多项式钟差建模预测模型存在预报精度较差的问题,通过对比AR模型和UC滑窗模型分别在短期和长期预报情况下的精度分布规律,结合钟差辅助三星定位的应用背景,分析了钟差预报误差对定位精度的影响,得出的结论说明UC滑窗模型适合短期预测,多项式模型更适合于长期预测。(3)针对星历龄期较短接收机开机后无法利用其计算卫星位置的问题,提出一种基于运动学定轨的卫星位置外推算法。首先利用过期星历拟合得到初始轨道,然后结合各类摄动力进行轨道外推,并与IGS给出的轨道作比较,给出算法性能的研究结果。实测数据结果表明,使用12小时数据拟合初值预报的情况下,6天内的径向误差在5m以内。最后,对研究的成果进行了总结,并对下一步即将开展的工作进行了展望。
[Abstract]:In the application environment of satellite navigation receiver, the usability is easily affected by various environmental factors, for example, the error correction ability of message checking in high error code environment is limited. In weak signal environment, message can not be received or updated, which will lead to the decline of availability. Aiming at the above problems, this paper studies the message integrity, receiver clock error modeling and satellite orbit extrapolation, studies the shortcomings of traditional processing methods, and puts forward the optimization design method. The research work in this paper is carried out in the following three aspects: (1) aiming at the problem that the traditional BCH error correction method can only correct 1-bit error code, a parameter error correction method based on orbit limitation is proposed. This method combines the physical meaning of message parameter, analyzes the limit range of parameter, and identifies and corrects the bit of error code. The simulation results show that the proposed error correction method can correct the error of more than 2 bits in the case of high bit error with limited parameter range. Finally, taking the ephemeris of Beidou system as an example, the bit error correction success rate of each message parameter is summarized. (2) the traditional polynomial clock error modeling and prediction model has the problem of poor prediction accuracy. By comparing the accuracy distribution of AR model and UC sliding window model in short and long term forecast, combined with the application background of clock difference to assist Samsung positioning, the influence of clock error prediction error on positioning accuracy is analyzed. The conclusion shows that the UC sliding window model is suitable for short-term prediction, and the polynomial model is more suitable for long-term prediction. (3) aiming at the problem that the ephemeris receiver can not be used to calculate the satellite position after it is turned on, This paper presents an extrapolation method of satellite position based on kinematic orbit determination. First, the initial orbit is obtained by using expired ephemeris fitting, then the orbit extrapolation is carried out by combining various kinds of perturbation forces, and compared with the orbit given by IGS, the research results of the algorithm performance are given. The measured data show that the radial error within 6 days is less than 5m when the 12 hour data is used to fit the initial prediction. Finally, the research results are summarized and the future work is prospected.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4
本文编号：2318764
[Abstract]:In the application environment of satellite navigation receiver, the usability is easily affected by various environmental factors, for example, the error correction ability of message checking in high error code environment is limited. In weak signal environment, message can not be received or updated, which will lead to the decline of availability. Aiming at the above problems, this paper studies the message integrity, receiver clock error modeling and satellite orbit extrapolation, studies the shortcomings of traditional processing methods, and puts forward the optimization design method. The research work in this paper is carried out in the following three aspects: (1) aiming at the problem that the traditional BCH error correction method can only correct 1-bit error code, a parameter error correction method based on orbit limitation is proposed. This method combines the physical meaning of message parameter, analyzes the limit range of parameter, and identifies and corrects the bit of error code. The simulation results show that the proposed error correction method can correct the error of more than 2 bits in the case of high bit error with limited parameter range. Finally, taking the ephemeris of Beidou system as an example, the bit error correction success rate of each message parameter is summarized. (2) the traditional polynomial clock error modeling and prediction model has the problem of poor prediction accuracy. By comparing the accuracy distribution of AR model and UC sliding window model in short and long term forecast, combined with the application background of clock difference to assist Samsung positioning, the influence of clock error prediction error on positioning accuracy is analyzed. The conclusion shows that the UC sliding window model is suitable for short-term prediction, and the polynomial model is more suitable for long-term prediction. (3) aiming at the problem that the ephemeris receiver can not be used to calculate the satellite position after it is turned on, This paper presents an extrapolation method of satellite position based on kinematic orbit determination. First, the initial orbit is obtained by using expired ephemeris fitting, then the orbit extrapolation is carried out by combining various kinds of perturbation forces, and compared with the orbit given by IGS, the research results of the algorithm performance are given. The measured data show that the radial error within 6 days is less than 5m when the 12 hour data is used to fit the initial prediction. Finally, the research results are summarized and the future work is prospected.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4
【参考文献】
相关期刊论文 前1条
1 李辉;李隆;乔建新;;基于AR模型的GPS授时分析[J];测绘技术装备;2012年01期
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