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Single Point Positioning with Sequential Least-Squares Filter and Estimated Real-Time Stochastic Model 被引量:7
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作者 WU Yun GUO Jiming 《Geo-Spatial Information Science》 2008年第1期13-16,共4页
To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using ... To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using GPS data and broadcast ephemeris, the numerical results indicating the accurate position estimates at sub-meter level are obtainable. 展开更多
关键词 GPS single point positioning functional model stochastic model sequential least-square filter
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Ultra-low power anti-crosstalk collision avoidance light detection and ranging using chaotic pulse position modulation approach 被引量:2
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作者 郝杰 巩马理 +4 位作者 杜鹏飞 卢宝杰 张帆 张海涛 付星 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期250-257,共8页
A novel concept of collision avoidance single-photon light detection and ranging(LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for r... A novel concept of collision avoidance single-photon light detection and ranging(LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for robust anti-crosstalk purposes. Besides, single-photon detectors(SPD) and time correlated single photon counting techniques are adapted, to sense the ultra-low power used for the consideration of compact structure and eye safety. Parameters including pulse rate, discrimination threshold, and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite ultra-low transmitting power. 展开更多
关键词 collision avoidance chaotic pulse position modulation time-correlated single photon counting anti-crosstalk
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A new approach of single epoch GPS posi- tioning for landslide monitoring
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作者 刘根友 朱耀仲 周蓉生 《Acta Seismologica Sinica(English Edition)》 CSCD 2005年第4期427-434,499,共9页
When the deformation of landslide becomes larger, the conventional static GPS surveying cannot satisfy the real-time requirement in landslide monitoring. In this paper we present a new method for single epoch GPS posi... When the deformation of landslide becomes larger, the conventional static GPS surveying cannot satisfy the real-time requirement in landslide monitoring. In this paper we present a new method for single epoch GPS posi- tioning combining with the accuracy of approximate coordinates of monitored station in landslide monitoring. This algorithm does not consider troublesome cycle-slip problem of carrier phase, and integer ambiguities can be solved at a single epoch, so the centimeter level accurate coordinates can be calculated instantaneously. By means of fil- tering or smoothing, this method can be extended to detect millimeter level deformation and velocity. In order to test the new method, low-cost single frequency receivers have been used in a real landslide, which happened in Jiangxi Province, China. 展开更多
关键词 deformation monitoring LANDSLIDE single epoch GPS positioning ambiguity resolution
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A state‑domain robust autonomous integrity monitoring with an extrapolation method for single receiver positioning in the presence of slowly growing fault
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作者 Zhangjun Yu Qiuzhao Zhang +2 位作者 Shubi Zhang Nanshan Zheng Keqiang Liu 《Satellite Navigation》 SCIE EI CSCD 2023年第3期198-209,共12页
Single receiver positioning has been widely used as a standard and standalone positioning technique for about 25 years.To detect the slowly growing faults caused by satellite and receiver clocks in single receiver pos... Single receiver positioning has been widely used as a standard and standalone positioning technique for about 25 years.To detect the slowly growing faults caused by satellite and receiver clocks in single receiver positioning,the Autonomous Integrity Monitoring with an Extrapolation method(AIME)was proposed based on the Kalman filter measurement domain.However,AIME was designed with the assumption of there is the same number of visible satellites at each epoch,which limits its application.To address this issue,this paper proposes a state-domain Robust Autonomous Integrity Monitoring with the Extrapolation Method(SRAIME).The slowly growing fault detection statistics is established based on the difference between the estimates of the state propagator and the posterior state estimation in Kalman filtering.Meanwhile,singular value decomposition is adopted to factor the covariance matrix of the difference to increase computational robustness.Besides,the relevant formulas of the proposed method are theoretically derived,and it is proven that the proposed method is suitable for any positioning model based on the Kalman filter.Additionally,the results of two experiments indicate that SRAIME can detect slowly growing faults in single receiver positioning earlier than AIME. 展开更多
关键词 GNSS single receiver positioning Slow growing fault State domain Fault detection
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Precision position measurement of single atom
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作者 Ziauddin Rahmatullah Almas Khan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2012年第10期75-78,共4页
Atom localization in a five-level atomic system under the effect of three driving fields and one standing wave field is suggested. A spontaneously emitted photon from the proposed system is measured in a detector. Pre... Atom localization in a five-level atomic system under the effect of three driving fields and one standing wave field is suggested. A spontaneously emitted photon from the proposed system is measured in a detector. Precision position measurement of an atom is controlled via phase and vacuum field detuning without considering the parity violation. 展开更多
关键词 Precision position measurement of single atom
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Preliminary assessment of the navigation and positioning performance of BeiDou regional navigation satellite system 被引量:130
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作者 YANG YuanXi LI JinLong +5 位作者 WANG AiBing XU JunYi HE HaiBo GUO HaiRong SHEN JunFei DAI Xian 《Science China Earth Sciences》 SCIE EI CAS 2014年第1期144-152,共9页
BeiDou regional navigation satellite system (BDS) also called BeiDou-2 has been in full operation since December 27, 2012. It consists of 14 satellites, including 5 satellites in Geostationary Orbit (GEO), 5 satel... BeiDou regional navigation satellite system (BDS) also called BeiDou-2 has been in full operation since December 27, 2012. It consists of 14 satellites, including 5 satellites in Geostationary Orbit (GEO), 5 satellites in Inclined Geosynchronous Orbit (IGSO), and 4 satellites in Medium Earth Orbit (MEO). In this paper, its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing, including satellite visibility, Position Dilution of Precision (PDOP) value, the precision of code and carrier phase measurements, the accuracy of single point positioning and differential position- ing and ambiguity resolution (AR) performance, which are also compared with those of GPS. It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm, respectively, which are comparable to those of GPS, and the accuracy of BDS single point positioning has satisfied the design requirement. The real-time kinematic positioning is also feasible by BDS alolae in the opening condition, since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS. The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km, which is on the same level with that of GPS. For the combined BDS and GPS, the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly. The accu- racy of BDS/GPS carrier phase differential positioning is about 35 and 20 % better than that of GPS for two short baseline tests in this study. The accuracy of BDS code differential positioning is better than 2.5 m. However it is worse than that of GPS, which may result from large code multipath errors of BDS GEO satellite measurements. 展开更多
关键词 BeiDou navigation satellite system service area dilution of precision precision of code and carrier phase measurement single point positioning code differential positioning ambiguity resolution carrier phase differential positioning
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Analysis of Galileo signal-in-space range error and positioning performance during 2015-2018 被引量:7
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作者 Weiwang Wu Fei Guo Jiazhu Zheng 《Satellite Navigation》 2020年第1期55-67,共13页
A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and cloc... A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and clock errors for Galileo show an obvious convergence trend over time. The annual statistical analyses show that the average root mean squares (RMSs) of SISRE for the Galileo constellation are 0.58 m (2015), 0.29 m (2016), 0.23 m (2017), and 0.22 m (2018). Currently, the accuracy of the Galileo signal-in-space is superior to that of the global positioning system (GPS) Block IIF (0.35 m). In addition, the orbit error accounts for the majority of Galileo SISRE, while the clock error accounts for approximately one-third of SISRE due to the high stability of the onboard atomic clock. Single point positioning results show that Galileo achieves an accuracy of 2-3 m, which is comparable to that of GPS despite the smaller number of satellites and worse geometry. Interestingly, the vertical accuracy of Galileo, which uses the NeQuick ionospheric model, is higher than that of GPS. Positioning with single frequency E1 and E5 show a higher precision than E5a and E5b signals. Regarding precise point positioning (PPP), the results indicate that a comparable positioning accuracy can be achieved among different stations with the current Galileo constellation. For static PPP, the RMS values of Galileo-only solutions are within 1 cm horizontally, and the vertical RMSs are mostly within 2 cm horizontally. For kinematic PPP, the RMSs of Galileo-only solutions are mostly within 4 cm horizontally and 6 cm vertically. 展开更多
关键词 GALILEO Signal in space range error(SISRE) single point positioning(SPP) Precise point positioning(PPP)
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