对美国定位、导航和授时(positioning,navigation and timing,PNT)领域的相关政策和整体目标进行了梳理,重点对GPS现代化改造、GPS与低轨通信卫星融合、建设eLoran系统和自主导航项目等重要PNT信息源的建设进展、服务能力和融合应用做...对美国定位、导航和授时(positioning,navigation and timing,PNT)领域的相关政策和整体目标进行了梳理,重点对GPS现代化改造、GPS与低轨通信卫星融合、建设eLoran系统和自主导航项目等重要PNT信息源的建设进展、服务能力和融合应用做了具体分析和总结,表明美国已经理清了PNT体系发展脉络,相关建设已进入实质阶段,同时对我国PNT信息源未来的发展、融合和建设提出了具体建议.展开更多
The concept of resilient positioning, navigation and timing (PNT) is described. The definition of resilient PNT is given, the relationship between integrated (or comprehensive) PNT and resilient PNT is analyzed, and i...The concept of resilient positioning, navigation and timing (PNT) is described. The definition of resilient PNT is given, the relationship between integrated (or comprehensive) PNT and resilient PNT is analyzed, and it is pointed out that the integrated PNT is the foundation of resilient PNT. Resilient PNT should be divided into resilient sensor integration, resilient functional model and resilient stochastic model. The strategy and principles of resilient integration of sensors are discussed. The resilient integration of sensors should be designed following the optimal, available, compatible and interoperable principles. The concepts of resilient functional model and possible modification strategies of the different functional models are also described. Several possible optimal routes for resilient stochastic model improvements are also set forth. It is pointed out that the optimal improvements of stochastic models for multi PNT sources should follow the same variance scale. At last, the resilient PNT data fusion for state parameters are given based on the resilient functional and stochastic models.展开更多
The maritime navigation accuracy requirements for radionavigation systems such as GPS are specified by the International Maritime Organization (IMO). Maritime navigation usually consists of three major phases identifi...The maritime navigation accuracy requirements for radionavigation systems such as GPS are specified by the International Maritime Organization (IMO). Maritime navigation usually consists of three major phases identified as Ocean/Coastal/Port approach/Inland waterway, in port navigation and automatic docking with an accuracy requirement that ranges from 10 m to 0.1 m. With the advancement in autonomous GPS positioning techniques such as Precise Point Positioning (PPP) and with the advent of the new IGS-Real-Time-Service (RTS), it is necessary to assess the possibility of a wider role of the PPP-based positioning technique in maritime applications. This paper investigates the performance of an autonomous real-time PPP-positioning solution by using the IGS- RTS service for maritime applications that require an accurate positioning system. To examine the performance of the real-time IGS-RTS PPP-based technique for maritime applications, kinematic data from a dual frequency GPS receiver is investigated. It is shown that the real-time IGS-RTS PPP-based GPS positioning technique fulfills IMO requirements for maritime applications with an accuracy requirement ranges from 10 m for Ocean/Coastal/Port approach/Inland waterways navigation to 1.0 m for in port navigation but cannot fulfill the automatic docking application with an accuracy requirement of 0.10 m. To further investigate the real-time PPP-based GPS positioning technique, a comparison is made between the real-time IGS-RTS PPP-based positioning technique and the real-time PPP-based positioning by using the predicted part of the IGS Ultra-Rapid products and the real-time GPS positioning technique with the Wide Area Differential GPS service (WADGPS). It is shown that the IGS-RTS PPP-based positioning technique is superior to the IGS-Ultra-Rapid PPP-based and WADGPS-based positioning techniques.展开更多
文摘对美国定位、导航和授时(positioning,navigation and timing,PNT)领域的相关政策和整体目标进行了梳理,重点对GPS现代化改造、GPS与低轨通信卫星融合、建设eLoran系统和自主导航项目等重要PNT信息源的建设进展、服务能力和融合应用做了具体分析和总结,表明美国已经理清了PNT体系发展脉络,相关建设已进入实质阶段,同时对我国PNT信息源未来的发展、融合和建设提出了具体建议.
文摘The concept of resilient positioning, navigation and timing (PNT) is described. The definition of resilient PNT is given, the relationship between integrated (or comprehensive) PNT and resilient PNT is analyzed, and it is pointed out that the integrated PNT is the foundation of resilient PNT. Resilient PNT should be divided into resilient sensor integration, resilient functional model and resilient stochastic model. The strategy and principles of resilient integration of sensors are discussed. The resilient integration of sensors should be designed following the optimal, available, compatible and interoperable principles. The concepts of resilient functional model and possible modification strategies of the different functional models are also described. Several possible optimal routes for resilient stochastic model improvements are also set forth. It is pointed out that the optimal improvements of stochastic models for multi PNT sources should follow the same variance scale. At last, the resilient PNT data fusion for state parameters are given based on the resilient functional and stochastic models.
文摘The maritime navigation accuracy requirements for radionavigation systems such as GPS are specified by the International Maritime Organization (IMO). Maritime navigation usually consists of three major phases identified as Ocean/Coastal/Port approach/Inland waterway, in port navigation and automatic docking with an accuracy requirement that ranges from 10 m to 0.1 m. With the advancement in autonomous GPS positioning techniques such as Precise Point Positioning (PPP) and with the advent of the new IGS-Real-Time-Service (RTS), it is necessary to assess the possibility of a wider role of the PPP-based positioning technique in maritime applications. This paper investigates the performance of an autonomous real-time PPP-positioning solution by using the IGS- RTS service for maritime applications that require an accurate positioning system. To examine the performance of the real-time IGS-RTS PPP-based technique for maritime applications, kinematic data from a dual frequency GPS receiver is investigated. It is shown that the real-time IGS-RTS PPP-based GPS positioning technique fulfills IMO requirements for maritime applications with an accuracy requirement ranges from 10 m for Ocean/Coastal/Port approach/Inland waterways navigation to 1.0 m for in port navigation but cannot fulfill the automatic docking application with an accuracy requirement of 0.10 m. To further investigate the real-time PPP-based GPS positioning technique, a comparison is made between the real-time IGS-RTS PPP-based positioning technique and the real-time PPP-based positioning by using the predicted part of the IGS Ultra-Rapid products and the real-time GPS positioning technique with the Wide Area Differential GPS service (WADGPS). It is shown that the IGS-RTS PPP-based positioning technique is superior to the IGS-Ultra-Rapid PPP-based and WADGPS-based positioning techniques.
