建立了GPS/INS紧组合定位模型,改正惯性器件误差及电离层折射误差,对不同组合观测量的误差影响进行了分析,构造不同观测值组合,提出了基于惯性信息辅助的GPS周跳自适应探测方法,分析了INS定位误差对周跳探测的影响,给出了周跳探测误报率及修复成功率评价指标,提出了一种周跳检测阈值自适应确定方法。利用实测组合导航试验数据验证本文的算法,文中模拟了不同的单历元多周跳及信号失锁条件,结果表明,在GPS信号完全失锁20 s内,该方法能准确检测和修复所有周跳,中断时间的延长降低了周跳修复的成功率;GPS信号部分失锁时,在模拟的90 s中断时段内仍能修复所有周跳;模拟了170历元的5 s间隔密集周跳,周跳探测成功率为100%,正确修复率为99.41%。
In order to improve the navigation performance and robustness, a GPS/INS tightly coupled model has been developed, the INS related bias and ionospheric errors were compensated and corrected, the impact of combination observations on cycle slip detection was investigated, and four combinations with the characteristics of longer wavelength, smaller noise and lower ionosphere effect were determined, then an innovative inertial aided adaptive cycle slip detection and correction algorithm based on the selected combination observations was presented, and the impact of INS positioning errors on cycle slip detection has been investigated, the probability of false alarm and success rate of cycle slip correction were utilized to enhance the integrity of cycle slip detection and correction, a new threshold determination criterion was provided to achieve robust cycle slip detection and correction. At last, a field test was utilized to verify and evaluate the performance of the proposed algorithm, multi-cycle slips and GPS gap scenarios were simulated, the results show that the scheme works effectively as long as the complete GPS data outage period is less than 20 second, the performance degrades as the outage period becomes longer; while during the partial data outage durations, the proposed scheme can fix the cycle slips correctly for the simulated 90 second partial outage due to the improved positioning accuracy, a total of 170 dense cycle slips (1 slip per 5 epochs)were introduced, it shows that all introduced cycle slips are successfully detected and the true fixing rate reaches 99.41%.
[1] XU Guochang. GPS: Theory, Algorithms and Applications[M]. 2nd ed. Berlin: Springer, 2007.
[2] BLEWITT G. An Automatic Editing Algorithm for GPS Data[J]. Geophysical Research Letters, 1990, 17(3):199-202.
[3] HAN S. Carrier Phase-based Long-range GPS Kinematic Positioning[D]. New South Wales: University of New South Wales, 1997.
[4] ZHANG Chengjun, XU Qifeng, LI Zuohu. Impoving Method of Cycle Slip Detection and Correction Based on Combination of GPS Pseudo Range and Carrier Phase Observations[J]. Acta Geodaetica et Cartographica Sinica, 2009, 38(5): 402-407. (张成军, 许其凤, 李作虎. 对伪距/相位组合量探测与修复周跳算法的改进[J]. 测绘学报, 2009, 38(5): 402-407.)
[5] YANG Yuanxi. Adaptive Navigation and Kinematic Positioning[M]. Beijing: Surveying and Mapping Press, 2006. (杨元喜. 自适应动态导航定位[M]. 北京: 测绘出版社, 2006.)
[6] HUANG Dingfa, ZHUO Jiancheng. Wavelet Analysis for Cycle Slip Detection and Reconstruction of GPS Carrier Phase Measurements[J]. Acta Geodaetica et Cartographica Sinica, 1997, 26(4): 352-357. (黄丁发, 卓健成. GPS相位观测值周跳检测的小波分析法[J]. 测绘学报, 1997, 26(4): 352-357.)
[7] YUAN Hong, WAN Weixing, NING Baiqi, et al. A New Cycle Slip Detection and Correction Method Using Triple Differences Solution[J]. Acta Geodaetica et Cartographica Sinica, 1998, 27(3): 189-194. (袁洪, 万卫星, 宁百齐, 等. 基于三差解检测与修复GPS载波相位周跳新方法[J]. 测绘学报, 1998, 27(3): 189-194.)
[8] HE Haibo, YANG Yuanxi. Detection of Successive Cycle Slips for GPS Kinematic Positioning[J]. Acta Geodaetica et Cartographica Sinica, 1999, 28(3): 199-203. (何海波, 杨元喜. GPS动态测量连续周跳检验[J]. 测绘学报, 1999, 28(3): 199-203.)
[9] LIU Zhizhao. A New Automated Cycle Slip Detection and Repair Method for a Single Dual-frequency GPS Receiver[J]. Journal of Geodesy, 2011, 85(3):171-183.
[10] DELACY M C, REGUZZONI M, SANSò F. Real-time Cycle Slip Detection in Triple-frequency GNSS[J]. GPS Solutions, 2012, 16(3):353-362.
[11] HUANG Lingyong, SONG Lijie, WANG Yan, et al. BeiDou Triple-frequency Geometry-free Phase Combination for Cycle-slip Detection and Correction[J]. Acta Geodaetica et Cartographica Sinica, 2012, 41(5): 763-768. (黄令勇, 宋力杰, 王琰, 等. 北斗三频无几何相位组合周跳探测与修复[J]. 测绘学报, 2012, 41(5): 763-768.)
[12] LI Jinlong, YANG Yuanxi, XU Junyi, et al. Real-time Cycle-slip Detection and Repair Based on Code-phase Combinations for GNSS Triple-frequency Un-differenced Observations[J]. Acta Geodaetica et Cartographica Sinica, 2011, 40(6): 717-722, 729. (李金龙, 杨元喜, 徐君毅, 等. 基于伪距相位组合实时探测与修复GNSS三频非差观测数据周跳[J]. 测绘学报, 2011, 40(6): 717-722, 729.)
[13] ALTMAYER C. Enhancing the Integrity of Integrated GPS/INS Systems by Cycle Slip Detection and Correction[C]//RILLINGS J. Proceedings of the IEEE Intelligent Vehicles Symposium, 2000. Dearborn: IEEE, 2000:174-179.
[14] DU Shuang, GAO Yang. Inertial Aided Cycle Slip Detection and Identification for Integrated PPP GPS and INS[J]. Sensors, 2012, 12(11):14344-14362.
[15] GREJNER-BRZEZINSKA D A, DA R, TOTH C. GPS Error Modeling and OTF Ambiguity Resolution for High-accuracy GPS/INS Integrated System[J]. Journal of Geodesy, 1998, 72(11): 626-638.
[16] SUN Hongxing. DGPS/INS Integrated Position and Attitude Determination and Its Application in MMS[D]. Wuhan: Wuhan University, 2004. (孙红星. 差分GPS/INS组合定位定姿及其在MMS中的应用[D]. 武汉: 武汉大学, 2004.)
[17] GE M, GENDT G, ROTHACHER M, et al. Resolution of GPS Carrier-phase Ambiguities in Precise Point Positioning (PPP) with Daily Observations[J]. Journal of Geodesy, 2008, 82(7):389-399.
[18] DONG D N, BOCK Y. Global Positioning System Network Analysis with Phase Ambiguity Resolution Applied to Crustal Deformation Studies in California[J]. Journal of Geophysical Research: Solid Earth (1978-2012), 1989, 94(B4):3949-3966.
[19] FENG Yanming. GNSS Three Carrier Ambiguity Resolution Using Ionosphere-reduced Virtual Signals[J]. Journal of Geodesy, 2008, 82(12):847-862.
[20] LI Bofeng, SHEN Yunzhong, ZHOU Zebo. A New Method for Medium and Long Range Three Frequency GNSS Rapid Ambiguity Resolution[J]. Acta Geodaetica et Cartographica Sinica, 2009, 38(4): 296-301. (李博峰, 沈云中, 周泽波. 中长基线三频GNSS模糊度的快速算法[J]. 测绘学报, 2009, 38(4): 296-301.)
[21] CHIANG K W, DUONG T T, LIAO J K. The Performance Analysis of a Real-time Integrated INS/GPS Vehicle Navigation System with Abnormal GPS Measurement Elimination[J]. Sensors, 2013, 13(8): 10599-10622.
[22] DING Weidong, WANG Jinling, RIZOS C, et al. Improving Adaptive Kalman Estimation in GPS/INS Integration[J]. Journal of Navigation, 2007, 60(3): 517-529.
