[1] Zhu Xuefen, Chen Xiyuan, Huang Haoqian, et al. Analysis of GPS ionospheric scintillation signal amplitudefading characteristics at low latitude [J]. Journal of Southeast University (English Edition), 2016, 32 (4): 484-488. [doi:10.3969/j.issn.1003-7985.2016.04.015]

Copy

Analysis of GPS ionospheric scintillation signal amplitudefading characteristics at low latitude()

低纬度地区GPS电离层闪烁信号幅度衰减特性分析

Share：

Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

32

Issue:

2016 4

Page:

484-488

Research Field:

Electromagnetic Field and Microwave Technology

Publishing date:

2016-12-20

Info

Title:

Analysis of GPS ionospheric scintillation signal amplitudefading characteristics at low latitude

低纬度地区GPS电离层闪烁信号幅度衰减特性分析

Author(s):

Zhu Xuefen^{1, 2}, Chen Xiyuan^{1, 2}, Huang Haoqian^{1, 2}, Chen Jianfeng³, Xu Bincheng^{1, 2}

¹School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China
²Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology of Ministry of Education, Southeast University, Nanjing 210096, China
³ Automotive Engineering Research Institute, Jiangsu University, Zhenjiang 212013, China

祝雪芬^{1, 2}, 陈熙源^{1, 2}, 黄浩乾^{1, 2}, 陈建锋³, 徐斌铖^{1, 2}

¹东南大学仪器科学与工程学院, 南京 210096; ²东南大学微惯性仪表与先进导航技术教育部重点实验室, 南京 210096; ³ 江苏大学汽车工程研究院, 镇江 212013

Keywords:

GPS L1;  ionospheric scintillation;  amplitude fading characteristics

GPS L1;  电离层闪烁;  幅度衰减特性

PACS:

TN967.1

DOI:

10.3969/j.issn.1003-7985.2016.04.015

Abstract:

The received satellite signal amplitude is attenuated greatly due to the strong ionospheric scintillation for low latitude regions, which causes the GPS tracking loop’s loss of lock, the positioning errors to increase, and navigation to be interrupted. To solve the above problems, a novel signal processing algorithm is proposed based on the GPS L1 software receiver during strong ionospheric scintillation using the multi-channel intermediate frequency(IF)data sampling system. Tens of thousands of fading events are obtained based on the signal intensity measurement. The amplitude fading characteristics in the low latitude region are analyzed, including fading duration, time separation between fades and the numbers of signal intensity fading events. The fading thresholds are set to be 15 and 10 dB, respectively. The main fading time is very short in -15 dB fading threshold, which generally is less than 20 ms. The main time separation between fades is less than 2 s in a single one-hour period from the time 23:00 to 24:00. Therefore, it has the characteristic of a short reacquisition time for the receiver designed to reduce the probability of simultaneous loss of lock for some satellites. Subsequently, the acquisition, tracking and PVT(position, velocity and time)calculations are completed by the custom-designed software receiver. The results show that the impact analysis of ionospheric scintillation on GPS amplitude attenuation in the low latitude region is helpful for designing the advanced tracking algorithm and to improve the robustness and accuracy of the GPS receiver.

针对低纬度地区强电离层闪烁发生时会造成接收的卫星信号幅度深度衰减, 导致GPS跟踪环路失锁、定位误差增大甚至导航中断的问题, 提出了一种基于多通道中频信号采集系统的GPS L1 软件接收机在经历强电离层闪烁时的信号处理算法.首先, 基于信号强度观测量得到的几万个衰减事件, 分析了低纬度地区的幅度衰减特性, 包括衰减时间、衰减间隔及衰减事件数, 其中衰减阈值分别设为-15和-10 dB.在-15 dB的衰减阈值下, 主要衰减时间非常短, 通常在20 ms以内, 在23:00~24:00之间, 主要衰减间隔小于2 s.故需要设计的接收机应具有短的重捕时间, 才能减少多个卫星同时失锁的可能性.然后用定制软件接收机来完成相关捕获、跟踪及PVT(位置、速度、时间)解算.结果表明:分析低纬度地区电离层闪烁对GPS幅度衰减的影响, 对于设计高级跟踪算法及提高GPS接收机的鲁棒性和精度将提供有益指导.

References:

[1] Carroll M J. Advanced GPS receiver algorithms for assured navigation during ionospheric scintillation[D]. Miami, USA: Computational Science and Engineering, Miami University, 2014.
[2] Carroll M J, Morton Y J, Vinande E. Triple frequency GPS signal tracking during strong ionospheric scintillations over Ascension Island[C]//2014 IEEE/ION Position, Location and Navigation Symposium. Monterey, CA, USA, 2014: 43-49. DOI: 10.1109/PLANS.2014.6851356.
[3] Kassabian N, Morton Y J. Extending integration time for Galileo tracking robustness under ionosphere scintillation[C]//2014 IEEE/ION Position, Location and Navigation Symposium. Monterey, CA, USA, 2014: 59-72. DOI:10.1109/plans.2014.6851358.
[4] Akala A O, Doherty P H, Carrano C S, et al. Impacts of ionospheric scintillations on GPS receivers intended for equatorial aviation applications[J]. Radio Science, 2012, 47(4): RS40071-RS400711. DOI: 10.1029/2012RS004995
[5] Wang J, Morton Y T. High-latitude ionospheric irregularity drift velocity estimation using spaced GPS receiver carrier phase time-frequency analysis[J]. IEEE Transactions on Geoscience and Remote Sensing, 2015, 53(11):6099-6113. DOI:10.1109/tgrs.2015.2432014.
[6] Seo J, Walter T, Chiou T Y, et al. Characteristics of deep GPS signal fading due to ionospheric scintillation for aviation receiver design[J]. Radio Science 2009, 44(1): RS0A16-1-RS0A16-10. DOI:10.1029/2008rs004077.
[7] Liu D, Feng J, Deng Z X, et al. Ionospheric scintillation effects on GPS positioning performance[J]. Chinese Journal of Radio Science, 2010, 25(4):702-710.
[8] Li G B, Zhu H, Shi W S. Influence of ionospheric scintillation on GPS capture performance[J]. Ship Electronic Engineering, 2012, 32(12):55-57.
[9] Jiao Y, Morton Y, Taylor S, et al. Characteristics of low-latitude signal fading across the GPS frequency bands[C]//Proceedings of ION GNSS. Tempa, FL, USA 2014:1203-1212.
[10] Jiao Y, Morton Y T, Taylor S, et al. Characterization of high-latitude ionospheric scintillation of GPS signals[J]. Radio Science, 2013, 48(6):698-708. DOI:10.1002/2013rs005259.
[11] Xu D, Morton Y. GPS carrier parameters characterization during strong equatorial ionospheric scintillation[C]//Proceedings of ION ITM. Dana Point, CA, USA, 2015:1-10.
[12] Xu D, Morton Y, Akos D, et al. GPS multi-frequency carrier phase characterization during strong equatorial ionospheric scintillation[C]//Proceedings of ION GNSS. Tampa, FL, USA, 2015: 1-10.
[13] Taylor S, Morton Y, Jiao Y, et al. An improved ionosphere scintillation event detection and automatic trigger for GNSS data collection systems[C]//Proceedings of ION ITM. Newport Beach, CA, USA 2012: 1563-1569.
[14] Zhang L, Morton Y. GPS carrier phase spectrum estimation for ionospheric scintillation studies[J]. Navigation, 2013, 60(2):113-122. DOI:10.1002/navi.33.

Memo

Memo:

Biography: Zhu Xuefen(1983—), female, doctor, associate professor, zhuxuefen@seu.edu.cn.
Foundation items: The National Natural Science Foundation for Young Scholars(No.51405203), Jiangsu Overseas Research and Training Program for University Prominent Young and Middle-Aged Teachers and Presidents, the Natural Science Foundation of Jiangsu Province(No.BK20160699).
Citation: Zhu Xuefen, Chen Xiyuan, Huang Haoqian, et al.Analysis of GPS ionospheric scintillation signal amplitude fading characteristics at low latitude[J].Journal of Southeast University(English Edition), 2016, 32(4):484-488.DOI:10.3969/j.issn.1003-7985.2016.04.015.

Common functions