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1.
GPS测量技术在测绘领域中的应用价值相当突出,有着不可替代的作用和地位。同时,基于CORS系统下GPS测量技术因为具备精准定位、高效率定位等特点,在行业当中被许多人士认可。对此,为了更好的提高GPS测量技术的应用价值,详细分析基于CORS系统下GPS测量技术,希望可以今后相关工作者提供理论性帮助。 相似文献
2.
The tightly coupled INS/GPS integration introduces nonlinearity to the measurement equation of the Kalman filter due to the use of raw GPS pseudorange measurements. The extended Kalman filter (EKF) is a typical method to address the nonlinearity by linearizing the pseudorange measurements. However, the linearization may cause large modeling error or even degraded navigation solution. To solve this problem, this paper constructs a nonlinear measurement equation by including the second-order term in the Taylor series of the pseudorange measurements. Nevertheless, when using the unscented Kalman filter (UKF) to the INS/GPS integration for navigation estimation, it causes a great amount of redundant computation in the prediction process due to the linear feature of system state equation, especially for the case with system state vector in much higher dimension than measurement vector. To overcome this drawback in computational burden, this paper further develops a derivative UKF based on the constructed nonlinear measurement equation. The derivative UKF adopts the concise form of the original Kalman filter (KF) to the prediction process and employs the unscented transformation technique to the update process. Theoretical analysis and simulation results demonstrate that the derivative UKF can achieve higher accuracy with a much smaller computational cost in comparison with the traditional UKF. 相似文献
3.
4.
《工程(英文)》2020,6(8):904-912
Using the FengYun-3C (FY-3C) onboard BeiDou Navigation Satellite System (BDS) and Global Positioning System (GPS) data from 2013 to 2017, this study investigates the performance and contribution of BDS to precise orbit determination (POD) for a low-Earth orbit (LEO). The overlap comparison result indicates that code bias correction of BDS can improve the POD accuracy by 12.4%. The multi-year averaged one-dimensional (1D) root mean square (RMS) of the overlapping orbit differences (OODs) for the GPS-only solution is 2.0, 1.7, and 1.5 cm, respectively, during the 2013, 2015, and 2017 periods. The 1D RMS for the BDS-only solution is 150.9, 115.0, and 47.4 cm, respectively, during the 2013, 2015, and 2017 periods, which is much worse than the GPS-only solution due to the regional system of BDS and the few BDS channels of the FY-3C receiver. For the BDS and GPS combined solution (also known as the GC combined solution), the averaged 1D RMS is 2.5, 2.3, and 1.6 cm, respectively, in 2013, 2015, and 2017, while the GC combined POD presents a significant accuracy improvement after the exclusion of geostationary Earth orbit (GEO) satellites. The main reason for the improvement seen after this exclusion is the unfavorable satellite tracking geometry and poor orbit accuracy of GEO satellites. The accuracy of BDS-only and GC combined solutions have gradually improved from 2013 to 2017, thanks to improvements in the accuracy of International GNSS Service (IGS) orbit and clock products in recent years, especially the availability of a high-frequency satellite clock product (30 s sampling interval) since 2015. Moreover, the GC POD (without GEO) was able to achieve slightly better accuracy than the GPS-only POD in 2017, indicating that the fusion of BDS and GPS observations can improve the accuracy of LEO POD. GC combined POD can significantly improve the reliability of LEO POD, simply due to system redundancy. An increased contribution of BDS to LEO POD can be expected with the launch of more BDS satellites and with further improvements in the accuracy of BDS satellite products in the near future. 相似文献
5.
Dah-Jing Jwo 《计算机、材料和连续体(英文)》2020,65(2):993-1014
The Global Positioning System (GPS) offers the interferometer for attitude
determination by processing the carrier phase observables. By using carrier phase
observables, the relative positioning is obtained in centimeter level. GPS interferometry
has been firstly used in precise static relative positioning, and thereafter in kinematic
positioning. The carrier phase differential GPS based on interferometer principles can
solve for the antenna baseline vector, defined as the vector between the antenna
designated master and one of the slave antennas, connected to a rigid body. Determining
the unknown baseline vectors between the antennas sits at the heart of GPS-based attitude
determination. The conventional solution of the baseline vectors based on least-squares
approach is inherently noisy, which results in the noisy attitude solutions. In this article,
the complementary Kalman filter (CKF) is employed for solving the baseline vector in
the attitude determination mechanism to improve the performance, where the receiversatellite double differenced observable was utilized as the measurement. By using the
carrier phase observables, the relative positioning is obtained in centimeter level.
Employing the CKF provides several advantages, such as accuracy improvement,
reliability enhancement, and real-time assurance. Simulation results based on the
conventional method where the least-squares approach is involved, and the proposed
method where the CKF is involved are compared and discussed. 相似文献
6.
为保证芦家峪风井井上下顺利贯通,并满足风井施工和工程安装精度要求,实施了地面GPS控制测量、井下控制导线测量、陀螺定向等工作,完成了芦家峪风井的联系测量任务,并完善了长平矿井的测量控制系统。 相似文献
7.
8.
GPS技术在巴东库区滑坡监测中的应用 总被引:1,自引:0,他引:1
本文在概述了GPS差分定位技术的理论,应用现状和进展的基础上,讨论了在库区运用GPS定位技术开展滑坡稳定性监测与研究的有关问题。基于在三峡库区巴东县13个滑坡体GPS监测的实际应用,总结了提高观测精度的几点措施,论述了GPS技术在滑坡稳定性研究中的可行性和有效性。 相似文献
9.
多路径效应对GPS精密定位的影响及消除方法分析 总被引:5,自引:0,他引:5
该文主要分析了多路径效应对GPS精密定位的影响以及利用信噪比消除多路径误差的方法,对提高GPS测量在精密定位中的精度具有一定应用价值。 相似文献
10.