Method for eliminating pseudolite near-far effect based on orthogonal subspace projection
-
摘要: 针对地基伪卫星系统中接收机受到远近效应影响无法正确捕获远场伪卫星信号这一问题，引入了基于正交子空间投影算法的捕获优化方法. 该方法应用于码分多址伪卫星信号，通过常规滑动相关法得到的强信号码相位和多普勒频移计算正交投影算子，将接收信号与其在强信号空间的投影相减得到弱信号空间并重新进行捕获，以消除强信号对弱信号的干扰. 实验结果表明：强弱信号在小于30 dB的功率比范围内，应用正交子空间投影法可以有效改善弱信号捕获性能. 这对拓宽地基伪卫星系统的有效工作范围、提升伪卫星接收机信号功率比容忍限度具有重大意义.
-
关键词:
- 地基伪卫星系统 /
- 码分多址(CDMA) /
- 远近效应 /
- 正交子空间投影 /
- 弱信号捕获概率
Abstract: Receivers in ground-based pseudolite systems are often affected by the near-far effect, causing failure acquisition of far-field pseudolite signals. An optimization method based on orthogonal subspace projection is introduced in this paper, which is applied to code division multiple access (CDMA) pseudolite signals. Firstly, strong-signal code phases and Doppler frequencies are obtained through conventional sliding correlation to calculate the orthogonal projection operator. Then the weak-signal space is obtained by the received signal subtracting its projection in the strong-signal space. Finally, the re-acquisition is done in the weak-signal space to eliminate of the interference of strong signals. The experimental result indicates that the orthogonal subspace projection can effectively improve weak-signal acquisition performance in the power ratio range of lower than 30 dB, which is of great importance to widen the effective working range of ground-based pseudolite systems and the limitation of pseudolite receivers’ signal power ratio tolerance. -
表 1 衰减器挂载方案
组别 挂载方案 1 1号星(20 ${\text{dB} }$)、8号星(30 ${\text{ dB} }$) 2 2号星(20 ${\text{ dB} }$)、7号星(20 ${\text{ dB} }$) 3 2号星(20 ${\text{ dB} }$)、7号星(40 ${\text{ dB} }$) 4 3号星(30 ${\text{ dB} }$)、6号星(60 ${\text{ dB} }$) 
下载: 导出CSV
-
[1] 郭树人, 刘成, 高为广, 等. 卫星导航增强系统建设与发展[J]. 全球定位系统, 2019, 44(2): 1-12. [2] 饶文利. 室内三维定位分类、方法、技术综述[J]. 测绘与空间地理信息, 2021, 44(3): 164-169. DOI: 10.3969/j.issn.1672-5867.2021.03.046 [3] 杨芳, 范金峰, 马军, 等. 导航增强伪卫星时间同步技术与精度分析[J]. 导航定位与授时, 2021, 8(3): 132-136. [4] 马鹏程, 唐小妹, 朱祥维, 等. 伪卫星应用中远近效应及其抑制技术分析[J]. 全球定位系统, 2016, 41(5): 28-34. [5] 王福军, 丁小燕, 谢维华, 等. 卫星导航干扰抑制与信号增强算法研究[J]. 全球定位系统, 2019, 44(4): 47-52. [6] MADHANI P H, AXElRAD P, KRUMVIEDA K, et al. Application of successive interference cancellation to the GPS pseudolite near-far problem[J]. IEEE transactions on aerospace and electronic systems, 2003, 39(2): 481-488. DOI: 10.1109/TAES.2003.1207260 [7] 刘旭, 姚铮, 吕红丽, 等. 基于SIC的伪卫星系统抗远近效应捕获算法研究[J]. 全球定位系统, 2020, 45(1): 12-18. [8] PATEL P, HOLTZMAN J. Performance comparison of a DS/CDMA system using a successive interference cancellation(IC) and parallel IC scheme under fading[C]// International Conference on Communications, 1994. DOI: 10.1109/ICC.1994.368852 [9] YANG C, MORTON J. Adaptive replica code synthesis for interference suppression in GNSS receivers[C]//International Technical Meeting of the Institute of Navigation, 2009: 131-138. [10] NUNES F D, SOUSA F M G. GNSS near-far mitigation through subspace projection without phase information[J]. IEEE transactions on aerospace and electronic systems, 2012, 48(3): 2746-2755. DOI: 10.1109/TAES.2012.6237626 [11] MORTON Y T, TSUI J B Y, LIN D M, et al. Assessment and handling of CA code self-Interference during weak GPS signal acquisition[C]//The 16th International Technical Meeting of the Satellite Division of the Institute of Navigation, 2003: 646-653. DOI: 10.1111/j.1365-2621.2010.02532.x [12] LIU X, YAO Z, LU M Q. Robust time-hopping pseudolite signal acquisition method based on dynamic Bayesian network[J]. GPS solutions, 2021, 25(2). DOI: 10.1007/s10291-020-01066-y [13] XU L. Research on signal design method of pseudolite "near-far effect" based on TDMA technique[C]// China Satellite Navigation Conference (CSNC), 2017: 417-429. [14] 刘宇航, 蔡伯根, 巴晓辉. 基于伪卫星的导航系统定位方法研究[C]//第十二届中国卫星导航年会, 2021: 7. [15] 谢超, 焦诚, 王乾. 一种跳时直接序列码分多址导航信号测距码优选方法[C]//第十二届中国卫星导航年会, 2021: 6. [16] 王迪, 陈光武, 刘射德. 基于伪卫星信号捕获原理的抗远近效应方法研究[J]. 测绘科学与仪器, 2017, 8(3): 228-237. [17] LI Y M, GAO J P, JI Y F, et al. Research on near-far Effect and anti-impact noise interference pseudo-code sequence blind estimation algorithm in pseudo satellite system[C]//The 3rd International Conference on Information Communication and Signal Processing (ICICSP), 2020: 413-417. DOI: 10.1109/ICICSP50920.2020.9232101 [18] CHEN M L, ZHAN X Q, YUAN W H, et al. Technical concerns of near-far effect in GNSS space service volume (SSV)[J]. Journal of aeronautics astronautics & aviation, 2016, 48(3): 149-156. DOI: 10.6125/16-0405-883 [19] 程建强, 杜丹, 周云, 等. 基于多阵元的室内伪卫星几何布局研究[J]. 无线电工程, 2020, 50(9): 762-768. DOI: 10.3969/j.issn.1003-3106.2020.09.009 [20] 汪夕琳, 周亚丽, 张佳. 基于伪码测距技术的无线定位系统设计与仿真[J]. 全球定位系统, 2018, 43(5): 84-90. -
点击查看大图
图(8) / 表(3)
计量
- 文章访问数: 257
- HTML全文浏览量: 69
- PDF下载量: 29
- 被引次数: 0
