Intermittent tracking algorithm and performance analysis of low earth orbit satellite navigation SNAP signals
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摘要: 随着卫星导航系统的快速发展,基于低地球轨道(low earth orbit, LEO)卫星的高精度可信导航已成为当前研究的热点. 然而,LEO卫星导航的安全可信问题一直阻碍其大规模应用,基于扩频码和导航电文(spreading code and navigation data based authentication proposal, SNAP)认证方案在解决上述问题中展现了良好势头. 本文的重点是解决SNAP信号的间歇跟踪算法及性能分析,并得到跟踪误差的解析表达式. 研究结果表明:由于间歇跟踪导致的误差累积服从高斯分布,其均值与多普勒频移变化率成正比,均方差可等价于载噪比(carrie noise ratio, CNR)的损失,相较载波环,码环受多普勒的影响较小. 本文的研究结果为间歇跟踪结构下接收机系统参数设计提供重要理论参考.
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关键词:
- GNSS /
- 间歇跟踪 /
- 低地球轨道(LEO)卫星 /
- 欺骗干扰 /
- 跟踪性能
Abstract: With the rapid development of satellite navigation systems, high-precision and trustworthy navigation based on low earth orbit (LEO) satellite has become a hot topic in current research. However, the safety and trustworthiness issues of LEO satellite navigation have always hindered its large-scale application. The authentication scheme based on spreading code and navigation data based authentication proposal (SNAP) has shown a good trend in solving the above problems. The focus of this paper is to solve the intermittent tracking algorithm and performance analysis of SNAP signals, and obtain the analytical expression of tracking error. The research results show that the error accumulation caused by intermittent tracking follows a Gaussian distribution, and its mean is proportional to the Doppler frequency shift rate, and the variance is equivalent to the loss of carrier-to-noise ratio. Compared with the carrier loop, the code loop is less affected by Doppler. The research results of this paper provide important theoretical reference for the design of receiver system parameters under intermittent tracking structure. -
表 1 仿真参数
场景 参数 LEO卫星高度 (1.0~2.0)×103 km MEO卫星高度 (1.5~2.5)×104 km 地球半径 6400 km 地球质量 6×1024 kg 观测间隔 1 ms 表 2 仿真参数
参数 值 扩频码 P 码 码速率 2.046 MHz $ c\left( {{t_1}} \right) $码长度 2046 chips $ c\left( {{t_2}} \right) $码长度 2046 chips 采样率 7.5 MHz 载波频率 1575.43 MHz 初始CNR 45 dB·Hz 码噪声带宽 1 Hz 载波噪声带宽 15 Hz 时分复用周期 1:1 ms -
[1] CHEN X, LUO R D, LIU T, YUAN H, et al. Satellite navigation signal authentication in GNSS: a survey on technology evolution, status, and perspective for BDS[J]. Remote sensing, 2023, 15(5): 1462. DOI: 10.3390/rs15051462 [2] 江旭东, 陈潇, 马满帅, 等. 典型低轨卫星星座导航增强性能对比性评估研究[J]. 全球定位系统, 2021, 46(2): 49-55. DOI: 10.12265/j.gnss.2020111202 [3] 张小红, 马福建. 低轨导航增强GNSS发展综述[J]. 测绘学报, 2019, 48(9): 1073-1087. DOI: 10.11947/j.AGCS.2019.20190176 [4] MENG L X, YANG L, YANG W, et al. A survey of GNSS spoofing and anti-spoofing technology[J]. Remote sensing, 2022(14): 4826. DOI: 10.3390/rs14194826 [5] YUAN M Z, TANG X M, OU G. Authenticating GNSS civilian signals: a survey[J]. Satellite navigation, 2023, 4(1): 6. DOI: 10.1186/s43020-023-00094-6 [6] 陈东桥. 基于新型OTP认证的GNSS导航电文加密认证技术研究[J]. 计算机产品与流通, 2021(3): 157-158. [7] 申成良, 郭承军. 卫星导航信号电文加密技术研究与评估[J]. 全球定位系统, 2018, 43(3): 7-12. [8] MOTELLA B, MARGARIA D, PAONNI M. SNAP: an authentication concept for the Galileo open service[C]//2018 IEEE/ION Position, Location and Navigation Symposium (PLANS), 2018. DOI: 10.1109/PLANS.2018.8373475 [9] 严涛, 田野, 李天, 等. CSK调制信号的跟踪方法[J]. 中国空间科学技术, 2023, 43(2): 117-127. DOI: 10.16708/j.cnki.1000-758X.2023.0026 [10] 陈玉君. 高动态卫星信号跟踪技术研究[J]. 电子技术与软件工程, 2021(16): 79-80. [11] 韩志凤, 刘建业, 李荣冰, 等. 北斗弱信号跟踪相干积分算法设计[J]. 控制与决策, 2018, 33(7): 1282-1286. DOI: 10.13195/j.kzyjc.2017.0197 [12] MARAGRIA D, MOTELLA B, ANGHILERI M, et al. Signal structure-based authentication for civil GNSS: recent solutions and perspectives[J]. IEEE signal processing magazine, 2017, 34(5): 27-37. DOI: 10.1109/MSP.2017.2715898 [13] 赵琳, 柏亚国, 丁继成, 等. 基于EKF的北斗B1C信号数据/导频联合跟踪方法[J]. 全球定位系统, 2020, 45(6): 1-9. DOI: 10.13442/j.gnss.1008-9268.2020.06.001 [14] 田野, 湛剑佳. 用于GNSS信号的可变相干积累时长的时频域结合捕获算法[J]. 全球定位系统, 2018, 43(4): 8-13. DOI: 10.13442/j.gnss.1008-9268.2018.04.002