系统工程与电子技术 ›› 2019, Vol. 41 ›› Issue (4): 701-707.doi: 10.3969/j.issn.1001-506X.2019.04.01

• 电子技术 • 上一篇    下一篇

基于ZF频率误差修正的GNSS信号捕获算法

王嘉宁1, 廉保旺1, 张苗苗2   

  1. 1. 西北工业大学电子信息学院, 陕西 西安 710072;
    2. 西安现代控制技术研究所, 陕西 西安 710065
  • 出版日期:2019-03-20 发布日期:2019-03-20

GNSS signal acquisition method based on ZF frequency error correction

WANG Jianing1, LIAN Baowang1, ZHANG Miaomiao2   

  1. 1. School of Electronics and Information, Northwestern Polytechnical University, Xi’an 710072, China;
    2. Xi’an Modern Control Technology Research Institute, Xi’an 71006, China
  • Online:2019-03-20 Published:2019-03-20

摘要:

在分析微弱信号条件下残余多普勒对全球导航卫星系统(global navigation satellite system,GNSS)信号捕获影响的基础上,提出了基于迫零(zero forcing,ZF)频率误差修正的GNSS信号捕获算法,该算法将ZF的频率修正与快速改进的双块零扩展(fast modified double block zero padding, FMDBZP)算法有机结合,从而获得高精度的频率估计结果,并将修正项实时引入本地环路振荡器,减少了由多普勒频率误差引起的相关功率损失,理论分析和仿真实验表明,在给定仿真条件下,该算法能明显提高捕获性能,捕获灵敏度相对于FMDBZP算法有1.2 dB的性能提升,残余多普勒频率估计的标准差小于2 Hz。

Abstract:

Based on the analysis of the influence of residual Doppler on the acquisition of weak global navigation satellite system (GNSS) signals, an acquisition algorithm based on zero forcing (ZF) frequency error correction is proposed. Integrating the frequency correction calculation step of the ZF algorithm with the fast modified double block zero padding (FMDBZP) algorithm organically, the high precision frequency estimation results are obtained; then, the correction terms are introduced to the local oscillator loop in real time. The theoretical analysis and simulation experiments show that the proposed algorithm can improve the acquisition sensitivity significantly. Under given simulation conditions, the proposed algorithm has a 1.2 dB performance improvement compared with that of the FMDBZP algorithm, and the standard deviation captured under the given integral time and the carrier noise ratio is less than 2 Hz.