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GNSS vulnerabilities:simulation,verification,and mitigation platform design

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Geo-Spatial Information Science 2013年第3期16卷 149-154页

作者： Xin ZHAO xingqun zhan Kai YAN School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

This paper introduces the design and construction of global navigation satellite systems(GNSS)vulnerability simulation,verification,and mitigation *** platform contains five modules:simulation of the signal-in-space environment,simulation of the vulnerabilities in the space segment,signal quality monitoring and data processing,vulnerability assessment and validation,and integrated *** provides a set of integrated simulations of different types of interference in the GNSS signal propagation domain,including electromagnetic interference,atmospheric disturbances,multipath,and interference in the inter-satellite *** paper focuses on the design of the main system modules and testing through an experimental *** results demonstrate both the effectiveness and realism of the modules and overall platform.

关键词： GNSS vulnerability spoofing jamming ionosphere delay multipath effect

Highly reliable relative navigation for multi-UAV formation flight in urban environments

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Chinese Journal of Aeronautics 2021年第7期34卷 257-270页

作者： Shizhuang WANG xingqun zhan Yawei ZHAI Cheng CHI Jiawen SHEN School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Formation flight of multiple Unmanned Aerial Vehicles(UAVs)is expected to bring significant benefits to a wide range of *** and reliable relative position information is a prerequisite to safely maintain a fairly close distance between UAVs and to achieve inner-system collision ***,Global Navigation Satellite System(GNSS)measurements are vulnerable to erroneous signals in urban canyons,which could potentially lead to catastrophic ***,on the basis of performing relative positioning with double differenced pseudoranges,this paper develops an integrity monitoring framework to improve navigation integrity(a measure of reliability)in urban *** the one hand,this framework includes a fault detection and exclusion scheme to protect against measurement *** accommodate urban scenarios,spatial dependence in the faults are taken into consideration by this *** the other hand,relative protection level is rigorously derived to describe the probabilistic error bound of the navigation *** indicator can be used to evaluate collision risk and to warn collision danger in real *** proposed algorithms are validated by both simulations and flight *** results quantitatively reveal the sensitivity of navigation performance to receiver configurations and environmental *** experimental results suggest high efficiency and effectiveness of the new integrity monitoring framework.

关键词： Collision avoidance Formation flight Global Navigation Satellite System(GNSS) Integrity Relative navigation Unmanned Aerial Vehicle(UAV)

Improved filtered-ε adaptive inverse control and its application on nonlinear ship maneuvering

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Journal of Systems Engineering and Electronics 2006年第4期17卷 788-792页

作者： Du Gang zhan xingqun zhang Weiming Zhong Shan Inst. of Aerospace Science & Technology Shanghai Jiaotong Univ. Shanghai 200030 P. R. China The Second Academy of China Aerospace Science and Industry Corporation Beijing 100854 P. R. China

The drawbacks of common nonlinear Filtered-ε adaptive inverse control （AIC） method, such as the unreliability due to the change of delay time and the faultiness existing in its disturbance control loop, are discussed. Based on it, the diagram of AIC is amended to accommodate with the characteristic of nonlinear object with time delay. The corresponding Filtered-ε adaptive algorithm based on RTRL is presented to identify the parameters and design the controller. The simulation results on a nonlinear ship model of ＂The R.O.V Zeefakker＂ show that compared with the previous scheme and adaptive PID control, the improved method not only keeps the same dynamic response performance, but also owns higher robustness and disturbance rejection ability, and it is suitable for the control of nonlinear objects which have higher requirement to the maneuverability under complex disturbance environment.

关键词： adaptive inverse control nonlinear control RTRL ship maneuvering NARX network.

A Robust Wi-Fi Fingerprinting Indoor Localization Coping with Access Point Movement

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Journal of Harbin Institute of Technology(New Series) 2017年第4期24卷 31-37页

作者： Yuan Liang xingqun zhan Wenhan Yuan Shuai Jing School of Aeronautics and Astronautics Shanghai Jiao Tong University

A Wi-Fi fingerprinting localization approach has attracted increasing attention in recent years due to the ubiquity of Access Point( AP). However,typical fingerprinting localization methods fail to resist accidental environmental changes,such as AP movement. In order to address this problem,a robust fingerprinting indoor localization method is initiated. In the offline phase,three attributes of Received Signal Strength Indication( RSSI) —average,standard deviation and AP's response rate—are computed to prepare for the subsequent computation. In this way,the underlying location-relevant information can be captured comprehensively. Then in the online phase, a three-step voting scheme-based decision mechanism is demonstrated, detecting and eliminating the part of AP where the signals measured are severely distorted by AP 's movement. In the following localization step,in order to achieve accuracy and efficiency simultaneously,a novel fingerprinting localization algorithm is applied. Bhattacharyya distance is utilized to measure the RSSI distribution distance,thus realizing the optimization of MAximum Overlapping algorithm( MAO). Finally,experimental results are displayed,which demonstrate the effectiveness of our proposed methods in eliminating outliers and attaining relatively higher localization accuracy.

关键词： Wi-Fi fingerprinting indoor localization Received Signal Strength Indication (RSSI) Access Point movement erroneous AP detecting algorithm

Applying Probabilistic Graphical Models in a GNSS Software Receiver

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Applying Probabilistic Graphical Models in a GNSS Software R...

第九届中国卫星导航学术年会

作者： Xin zhang Lingxiao Zheng xingqun zhan School of Aeronautics and Astronautics Shanghai Jiao Tong University

A probabilistic graphical modelling approach to the parameter and state estimation problems in a GNSS receiver is proposed. This method turns out to be universal and comprehensive since as a framework it can accommodate both a traditional software receiver with scalar tracking loop(STL) and one with a vector tracking loop(VTL). It can even be extended to a multi-sensor integration setting and serves as a candidate software architecture for All Source Positioning and Navigation(ASPN).

关键词： PGM GNSS INS integration sensor

Robust GNSS triple-carrier joint estimations under strong ionosphere scintillation

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Robust GNSS triple-carrier joint estimations under strong io...

Evaluation of Satellite Acceleration Determination Methods in GNSS/INS Deep Integration

第十一届中国卫星导航年会

作者： Rong Yang xingqun zhan Jihong Huang School of Aeronautics and Astronautics Shanghai Jiao Tong University

In this paper, we proposed a tri-frequency joint estimation algorithm to address the loss of lock issues during strong ionospheric scintillations. This algorithm utilizes the frequency dependency to a

关键词： ionosphere scintillation triple frequency GNSS carrier tracking

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Evaluation of Satellite Acceleration Determination Methods i...

第十四届中国卫星导航年会

作者： Wei Gao xingqun zhan Rong Yang Shanghai Jiao Tong University

Deep integration is a deep level integration of Global Navigation Satellite System(GNSS) and Inertial Navigation System(INS). One of the key steps in deep integration is to find out the motion dynamics between the receiver and satellite in line-of-sight direction and build the connection with the carrier tracking loop of the receiver. The carrier loops have high frequency of updating, while fragile to lose lock. As a result, timely and accurate satellite acceleration information is especially important in deep integration. Similar to the satellite velocity determination method, the derivative method can be applied to calculate satellite acceleration based on the second order derivative of the six orbital elements and corresponding correction terms, while the calculation formulas are relatively complex. The kinematic method and the difference method use the kinematic equations and velocity difference to solve the satellite acceleration respectively, which reduces the computation load significantly. Based solely on broadcast ephemeris, this paper implements three real-time satellite acceleration determination methods, namely derivative, kinematic, and difference method. All above methods are evaluated on calculation load, calculation accuracy, and application range with corresponding precise ephemeris as reference acceleration by Chebyshev interpolation. For the requirements of satellite acceleration determination in GNSS/INS deep integration, the method evaluation results in this paper can be used as an important reference for strategies selection under different scenarios.

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Spatiotemporal Alignment and Measurement Accuracy Evaluation of New Point Cloud Devices in Autonomous Driving

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Spatiotemporal Alignment and Measurement Accuracy Evaluation...

第十四届中国卫星导航年会

作者： Jiahui Liu Xin zhang xingqun zhan School of Aeronautics and Astronautics Shanghai Jiao Tong University

Despite the increasing applications of point cloud, the measurement accuracy evaluation of point cloud devices is usually neglected, causing precision loss of missions. This paper is based on the synchronization and extrinsic calibration of different modalities of sensors, obtaining spatiotemporal alignment accuracy using the cumulative distribution function, and the measurement model for integrity monitoring. After spatial alignment, we proposed the static and dynamic measurement accuracy evaluation approaches. The static accuracy evaluation is based on standstill landmarks and sensors, using the ground truth obtained by integrated navigation to acquire measurements error. The dynamic accuracy evaluation requires the sensor moving with a trajectory, and establishing the surroundings’ map using SLAM process as the ground truth, then the sensor measurement error could be evaluated. Experiments of new point cloud devices such as high-resolution solid-state LiDAR and low resolution 4D radar demonstrate the effectiveness of our method.

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Integrity Monitoring of PPP-RTK based on Multiple Hypothesis Solution Separation

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Integrity Monitoring of PPP-RTK based on Multiple Hypothesis...

第十三届中国卫星导航年会

作者： Shizhuang Wang xingqun zhan Yingchao Xiao Yawei Zhai Shanghai Jiao Tong University GeeSpace Co.Ltd

Recent progress for high-precision positioning mainly focused on PPP-RTK,which is a precise point positioning(PPP) technique based on a realtime kinematic(RTK) ***-RTK is expected to become the mainstream positioning solution for various intelligent transportation systems(ITS) such as autonomous driving,unmanned aerial vehicles,and urban air *** studies on PPP-RTK mainly focused on improving navigation ***,for safety-critical applications,integrity is also an important performance *** PPP-RTK is usually implemented using a Kalman filter(KF),the well-known integrity monitoring schemes developed for leastsquares-based systems cannot be directly applied to *** considering the time-sequential nature of KF,we propose a user-end integrity monitoring scheme of PPP-RTK based on multiple hypothesis solution separation(MHSS) to offer high-reliability and high-precision position solutions with realtime integrity *** proposed scheme includes two key functions:real-time fault detection and rigorous protection level(PL) *** scheme captures both the faults from PPP-RTK service products and those faults introduced at the user *** are carried out with real data and simulated fault *** results suggest the effectiveness of the proposed scheme and indicate that multi-constellation PPP-RTK can offer position solutions with decimeter-level PLs(integrity risk:10

关键词： PPP-RTK Integrity Monitoring Fault Detection Protection Level