Urban GNSS Reliability and Signal Error Modeling

urban GNSSmultipathNLOSdiffractionDoppler consistencyheavy-tailed errorsmeasurement reliabilityuncertainty modeling

Pillar lead: Li-Ta Hsu

Dense cities are not an exception case for GNSS; they are the stress test. We study how GNSS measurements fail — NLOS reception, multipath, diffraction, Doppler distortion, heavy-tailed errors — and detect and quantify these failures at the measurement layer before they corrupt downstream estimation.

$Conventional GNSS trusts every measurement equally, so urban NLOS, multipath and diffraction corrupt the fix; IPNL instead models reliability at the signal layer so each measurement carries a trust tag the rest of the navigation stack can use.$

The goal is not only to correct bad measurements but to model their reliability, so the rest of the navigation stack knows when to trust them. This pillar is the measurement-layer foundation for the Environment-Aware, Optimization-Based Estimation, and Integrity pillars.

Related Projects

Multi-Agent Collaborative GNSS for Intelligent Transportation Systems completed
UrbanNav active
Robust GNSS Navigation for Urban Air Traffic Management active
UrbanLoco maintained
GraphGNSSLib active
3D Map-Aided GNSS (3DMA) for Smartphone and IoT active
Environment-Aware GNSS for UAS and Autonomous Driving active
GPS_VT_SDR: Receiver-Level GNSS Signal Processing Platform archived-influential

Related Publications

2026 (5)

patent

Hsu, L. T& Wen, W (2026).3D LiDAR Aided GNSS and the Method for NLOS Detection and Correction (CA 3,156,087). Canadian Intellectual Property Office (CIPO).

journal Q1

Fang, J., Bing, Xu, Liu, X., & Hsu, L.-T. (2026).Multipath Parameter Estimation Using GNSS Receiver Doppler Measurements. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2026.3683035

journal Q1

Yan, P., Zhan, X., Sun, R., & Hsu, L.-T. (2026).Credible Uncertainty Quantification Under Noise and System Model Mismatch in Localization Systems. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2026.3682809

journal Q1

Tsang, C.-L., Hoi-Wah, Ng, Luo, Y., Hai, Di, & Hsu, L.-T. (2026).Ultra-low power GNSS L5 band snapshot positioning: A two step approach. IEEE Internet of Things Journal. https://doi.org/10.1109/jiot.2026.3680038

journal

Hoi-Wah, Ng, Hoi-Fung, Ng, Hsu, L.-T., & Rizzo, J.-R. (2026).Three-Dimensional Mapping-Aided Global Navigation Satellite System in Global Navigation Satellite System-Accessible Indoor Areas. Sensors. https://doi.org/10.3390/s26031058

2025 (11)

book

Hsu, L. T., Zhang, G., & F., N. H. (2025).Chapter: Map-Aided GNSS Positioning. Springer Publishers Inc.

patent

Hsu, L. T& Wen, W (2025).3D LiDAR Aided GNSS and the Method for NLOS Detection and Correction (ZL 2022 1 0905688.2). China National Intellectual Property Administration (CNIPA).

patent

Hsu, L. T& Wen, W (2025).3D LiDAR Aided GNSS and the Method for NLOS Detection and Correction (HK 40077647). Hong Kong Intellectual Property Department.

journal Q1

Yan, P., Hu, Y., Wen, W., & Hsu, L. T. (2025).Multiple Faults Isolation For Multi-Constellation GNSS Positioning through Incremental Expansion of Consistent Measurements. IEEE Sensors Journal. https://doi.org/10.1109/jsen.2024.3524434

journal Q1

Ng, H. F., Zhong, Q., Groves, P., & Hsu, L. T. (2025).Grid-based 3DMA GNSS with clustering and Doppler velocity using factor graph optimisation. The Journal of Navigation. https://doi.org/10.1017/s0373463325000220

journal Q1

Liu, X., Wen, W., Huang, F., Gao, H., Wang, Y., & Hsu, L. T. (2025).3-D LiDAR-Aided GNSS NLOS Mitigation for Reliable GNSS-RTK Positioning in Urban Canyons. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2025.3629836

journal Q1

Yang, P., Wen, W., Bai, S., & Hsu, L. T. (2025).Tightly joined positioning and control model for unmanned aerial vehicles based on factor graph optimization. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2025.3589556

journal Q1

Liu, X., Wen, W., Zhang, L., & Hsu, L. T. (2025).3D LiDAR Aided GNSS NLOS Correction by Direction-of-Arrival Estimation Using Doppler Measurements in Urban Canyons. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2025.3596582

conference

Zhengdao, Li, Yan, P., Wen, W., & Hsu, L.-T. (2025).Paired Cauchy-Gaussian overbound for not symmetric unimodal heavy-tailed distributions. 2025 IEEE/ION Position, Location and Navigation Symposium (PLANS). https://doi.org/10.1109/PLANS61210.2025.11028215

conference

Huang, F., Zhong, Y., Chen, H., Dongzhe, Su, Jin, Wu, Wen, W., & Hsu, L.-T. (2025).Roadside GNSS Aided Multi-Sensor Integrated System for Vehicle Positioning in Urban Areas. 2025 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). https://doi.org/10.1109/IROS60139.2025.11246475

conference

Zhong, Y., Hoi-Fung, Ng, Hsu, L.-T., & Wen, W. (2025).GNSS/Map Integration with Batch Factor Graph Optimization for Reliable Trajectory Estimation in Urban Canyon. 2025 IEEE/ION Position, Location and Navigation Symposium (PLANS). https://doi.org/10.1109/PLANS61210.2025.11028209

2024 (33)

patent

Hsu, L. T& Wen, W (2024).3D LiDAR Aided GNSS and the Method for NLOS Detection and Correction (US 12,123,961 B2). U.S. Patent and Trademark Office. https://patents.google.com/patent/US12123961B2

patent

Liu, X, Wen, W, Liu, J, & Hsu, L. T (2024).NLOS Error Correction Method, Apparatus, Terminal and Storage Medium (一种非视距误差修正方法、装置、终端及存储介质) (CN 202410345048.X). China National Intellectual Property Administration (CNIPA).

journal Q1

Xin, S., Geng, J., & Hsu, L. T. (2024).Factor Graph Optimization-based GNSS PPP-RTK: An Alternative Platform to Study Urban GNSS Precise Positioning. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2024.3360380

journal Q1

Zhong, Y., Hu, R., Bai, X., Li, X., Hsu, L. T., & Wen, W. (2024).Enhancing GNSS Positioning Accuracy for Road Monitoring Systems: A Factor Graph Optimization Approach Aided by Geospatial Information. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2024.3369156

journal Q1

Ye, M., Zhang, G., & Hsu, L. T. (2024).Building Model Rectification Using GNSS Reflectometry. IEEE Geoscience and Remote Sensing Letters. https://doi.org/10.1109/lgrs.2024.3373639

journal Q1

Xu, P., Zhang, G., Zhong, Y., Yang, B., & Hsu, L. T. (2024).A Framework for Graphical GNSS Multipath and NLOS Mitigation. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2024.3374819

journal Q1

Vicenzo, S., Xu, B., Xu, H., & Hsu, L. T. (2024).GNSS direct position estimation-inspired positioning with pseudorange correlogram for urban navigation. GPS Solutions. https://doi.org/10.1007/s10291-024-01627-5

journal Q1

Zhang, L., Ng, H. F., Zhang, G., & Hsu, L. T. (2024).Ray-Tracing Correction for GNSS Velocity Estimation Using Doppler Frequency: A Feasibility Analysis. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2024.3385033

journal Q1

Xu, P., Zhang, G., Yang, B., & Hsu, L. T. (2024).Machine Learning in GNSS Multipath/NLOS Mitigation: Review and Benchmark. IEEE Aerospace and Electronic Systems Magazine. https://doi.org/10.1109/maes.2024.3395182

journal Q1

Zhong, Y., Wen, W., & Hsu, L. T. (2024).Trajectory Smoothing Using GNSS/PDR Integration Via Factor Graph Optimization in Urban Canyons. IEEE Internet of Things Journal. https://doi.org/10.1109/jiot.2024.3396360

journal Q1

Jin, R., Zhang, G., Hsu, L. T., & Hu, Y. (2024).A Survey on Cooperative Positioning Using GNSS Measurements. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2024.3397879

journal Q1

Bai, X.& Hsu, L. T. (2024).GNSS/Visual/IMU/Map Integration Via Sliding Window Factor Graph Optimization for Vehicular Positioning in Urban Areas. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2024.3412208

journal Q1

Qi, X., Xu, B., Wang, Z., & Hsu, L. T. (2024).Random forest-based multipath parameter estimation. GPS Solutions. https://doi.org/10.1007/s10291-024-01667-x

journal Q1

Zheng, X., Wen, W., & Hsu, L. T. (2024).Tightly-coupled visual/inertial/map integration with observability analysis for reliable localization of intelligent vehicles. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2024.3419101

journal Q1

Xu, H., Zhang, G., & Hsu, L. T. (2024).Urban Building Updates Monitoring Based on Sky Visibility Estimation From Satellite Signals. IEEE Internet of Things Journal. https://doi.org/10.1109/jiot.2024.3434684

journal Q1

Zhang, Z., Xu, P., Zhang, G., & Hsu, L. T. (2024).GNSS-based Environment Retrieval: A Deep Learning Approach for Fine-grained Environment Perception. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2024.3440645

journal Q1

Yan, P., Zhong, Y., & Hsu, L. T. (2024).Principal Gaussian Overbound for Heavy-tailed Error Bounding. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2024.3448405

journal Q1

Yan, P., Xia, X., Brizzi, M., Wen, W., & Hsu, L. T. (2024).Subspace-based Adaptive GMM Error Modeling for Fault-Aware Pseudorange-based Positioning in Urban Canyons. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2024.3450198

journal Q1

Xia, X., Wen, W., & Hsu, L. T. (2024).Integrity-Constrained Factor Graph Optimization for GNSS Positioning in Urban Canyons. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.33012/navi.660

journal Q1

Fang, J., Zhang, L., Zhang, G., Xu, B., & Hsu, L. T. (2024).Characterization and Validation of GNSS Multipath-Induced Doppler Measurement Error. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2024.3487132

journal Q1

Zhang, L., Ng, H. F., Zhong, Y., Zhang, G., & Hsu, L. T. (2024).GNSS Doppler Velocity Estimation Aided by 3D Mapping Database. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2024.3486448

conference

Zhou, J., Lian, J., Zhang, G., & Hsu, L.-T. (2024).Performance Assessment of GNSS Positioning in Different Vegetated Environments. Proceedings of the ION 2024 Pacific PNT Meeting. https://doi.org/10.33012/2024.19656

conference

Bai, S., Wen, W., Yue, Yu, & Hsu, L.-T. (2024).Invariant Extended Kalman Filtering for Pedestrian Deep-Inertial Odometry. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. https://doi.org/10.5194/isprs-archives-xlviii-4-2024-607-2024

conference

Fang, J., Zhang, L., Zhang, G., Bing, Xu, & Hsu, L.-T. (2024).Modeling and Validation of GNSS Multipath-Induced Doppler Tracking Error. The International Technical Meeting of the The Institute of Navigation. https://doi.org/10.33012/2024.19549

conference

Yan, P., Zhong, Y., & Hsu, L.-T. (2024).Bounding the Heavy-Tailed Pseudorange Error by Leveraging Membership Weights Analysis of Gaussian Mixture Model. ION Pacific PNT. https://doi.org/10.33012/2024.19604

conference

Debiao, Lu, Wang, H., Cai, B., Wang, J., Liu, J., Zhang, G., & Hsu, L.-T. (2024).BDS for Train Localization Performance Forecast in Railway Environments Using Machine Learning. ION Pacific PNT. https://doi.org/10.33012/2024.19652

conference

Penghui, Xu& Hsu, L.-T. (2024).AutoW: Self-Supervision Learning for Weighting Estimation in GNSS Positioning. ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation. https://doi.org/10.33012/2024.19896

conference

Mingda, Ye, Zhang, G., & Hsu, L.-T. (2024).3DMA GNSS Positioning with Multipath Signals in Urban Areas: Methodology and Preliminary Results. ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation. https://doi.org/10.33012/2024.19770

conference

Hoi-Fung, Ng, Penghui, Xu, Zhong, Y., Zhang, G., Wen, W., & Hsu, L.-T. (2024).DGNSS Corrected Pseudorange and Time-Differenced Carrier Phase (TDCP) Measurements using Differentiable Factor Graph Optimization (DFGO). ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation. https://doi.org/10.33012/2024.19908

conference

Vicenzo, S., Xin, Qi, Bing, Xu, & Hsu, L.-T. (2024).Machine Learning Assisted GNSS Direct Position Estimation for Urban Environments Applications. The International Technical Meeting of the The Institute of Navigation. https://doi.org/10.33012/2024.19567

conference

Hai, Di, Tsang, C. L., Zhang, G., & Hsu, L.-T. (2024).GNSS Measurement Performance in Vegetation Environments: Assessment and Analysis in Signal Processing Level. ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation. https://doi.org/10.33012/2024.19880

conference

Yuan, Li, Liu, X., Wen, W., Hsu, L.-T., Yuan, Y., Bian, G., & Chen, Q. (2024).Factor Graph Optimization Based Multi Epoch Ambiguity Resolution for GNSS RTK and its Evaluation in Hong Kong Urban Canyons. ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation. https://doi.org/10.33012/2024.19805

conference

Lian, J., Zhou, J., Luo, Y., Zhang, G., & Hsu, L.-T. (2024).Improving GNSS Positioning in Challenging Urban Areas by Digital Twin Database Correction. 2024 14th International Conference on Indoor Positioning and Indoor Navigation (IPIN). https://doi.org/10.1109/IPIN62893.2024.10786144

2023 (33)

patent

Hsu, L. T& Wen, W (2023).3D Vision Aided GNSS Real-time Kinematic Positioning for Autonomous Systems in Urban Canyons (PCT/CN2023/087717 · US 18/856,932 · HK 62024100104.4 · CN 202380033788.3 · CA 3247676). WIPO / USPTO / HKIPD / CNIPA / CIPO (multi-jurisdiction PCT family).

patent

Gong, Z, Bao, X, B, Y., Y, G., Hsu, L. T, & Wen, W (2023).Vehicle Position Enhancement System and Method (车载位置增强系统及方法) (CN 202310289415.4). China National Intellectual Property Administration (CNIPA). https://patents.google.com/patent/CN116660938A

journal

Marais, J., Crespillo, O. G., & Hsu, L.-T. (2023).Editorial: Enhanced GNSS-based localization solutions with artificial intelligence. Frontiers in Robotics and AI. https://doi.org/10.3389/frobt.2023.1265989

journal

Jia, Q., Luo, Y., Bing, Xu, Hsu, L.-T., & Renbiao, Wu (2023).A robust vector tracking loop structure based on potential bias analysis. Chinese Journal of Aeronautics. https://doi.org/10.1016/j.cja.2023.11.013

journal Q1

Luo, Y., Hsu, L. T., Jiang, Y., Liu, B., Zhang, Z., Xiang, Y., & El-Sheimy, N. (2023).High-Accuracy Absolute-Position-Aided Code Phase Tracking Based on RTK/INS Deep Integration in Challenging Static Scenarios. Remote Sensing. https://doi.org/10.3390/rs15041114

journal Q1

Yan, P., Wen, W., & Hsu, L. T. (2023).Integration of Vehicle Dynamic Model and System Identification Model for Extending the Navigation Service Under Sensor Failures. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2023.3273185

journal Q1

Chang, J., Huang, F., Zhang, L., Xu, D., & Hsu, L. T. (2023).Selection of Areas for Effective GNSS Spoofing Attacks to a Vehicle-mounted MSF System based on Scenario Classification Models. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2023.3279831

journal unranked

Tsang, C. L., Luo, Y., Xu, B., & Hsu, L. T. (2023).C/N0 Assessment Based on GPS L5/L1C/A Signal Acquisition in Open-Sky/Light-Urban/Dense-Urban/Indoor Environments with Extended Coherent Integration Time. Journal of Aeronautics, Astronautics and Aviation.

journal Q1

Zhang, L., Wen, W., Hsu, L. T., & Zhang, T. (2023).An Improved Inertial Preintegration Model in Factor Graph Optimization for High Accuracy Positioning of Intelligent Vehicles. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2023.3282623

journal Q1

Zhang, Z., Li, Y., He, X., & Hsu, L. (2023).Resilient GNSS real-time kinematic precise positioning with inequality and equality constraints. GPS Solutions. https://doi.org/10.1007/s10291-023-01454-0

journal Q1

Fang, J., Yue, J., Xu, B., & Hsu, L. T. (2023).A post-correlation graphical way for continuous GNSS spoofing detection. Measurement. https://doi.org/10.1016/j.measurement.2023.112974

journal Q1

Luo, Y., Hsu, L. T., Tsang, C. L., & El-Sheimy, N. (2023).An Unassisted Super-Resolution Satellite Navigation Receiver Using GPS L5 Signals. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2023.3293782

journal Q1

Dey, A., Iyer, K., Xu, B., Sharma, N., & Hsu, L. T. (2023).Performance Evaluation of Vectorized NavIC Receiver Using Improved Dual-Frequency NavIC Measurements. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2023.3295020

journal Q1

Luo, Y., Hsu, L. T., & El-Sheimy, N. (2023).A Baseband MLE for Snapshot GNSS Receiver Using Super-Long-Coherent Correlation in a Fractional Fourier Domain. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.33012/navi.588

journal Q1

Wen, W., Bai, X., & Hsu, L. T. (2023).3D Vision Aided GNSS Real-Time Kinematic Positioning for Autonomous Systems in Urban Canyons. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.33012/navi.590

journal Q1 Featured

Liu, X., Wen, W., & Hsu, L. T. (2023).GLIO: Tightly-coupled gnss/lidar/imu integration for continuous and drift-free state estimation of intelligent vehicles in urban areas. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2023.3323648

journal Q1 Featured

Xu, P., Zhang, G., Yang, B., & Hsu, L. T. (2023).PositionNet: CNN-based GNSS positioning in urban areas with residual maps. Applied Soft Computing. https://doi.org/10.2139/ssrn.4194604

journal Q1

Chang, J., Zhang, Y., Fan, S., Huang, F., Xu, D., & Hsu, L. T. (2023).An Anti-spoofing Model based on MVM and MCCM for a Loosely-coupled GNSS/INS/LiDAR Kalman Filter. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2023.3335356

journal Q1

Chen, P., Guan, W., Huang, F., Zhong, Y., Wen, W., Hsu, L. T., & Lu, P. (2023).ECMD: An Event-Centric Multisensory Driving Dataset for SLAM. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2023.3339144

journal Q1 Featured

Hsu, L. T., Huang, F., Ng, H. F., Zhang, G., Zhong, Y., Bai, X., & Wen, W. (2023).Hong Kong UrbanNav: An open-source multisensory dataset for benchmarking urban navigation algorithms. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.33012/navi.602

journal Q1

Ng, H. F., Hsu, L. T., & Zhang, G. (2023).Multi-Epoch Kriging-Based 3D Mapping-Aided GNSS and Doppler Measurement Fusion using Factor Graph Optimization. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.33012/navi.617

journal Q1

Li, Z., Lee, P. H., Hung, T. H. M., Zhang, G., & Hsu, L. T. (2023).Intelligent Environment-Adaptive GNSS/INS Integrated Positioning with Factor Graph Optimization. Remote Sensing. https://doi.org/10.3390/rs16010181

conference

Zhong, Y., Wen, W., & Hsu, L.-T. (2023).Towards Accurate Vehicle-to-Pedestrian Relative Positioning Aided by Inter-Frame and Inter-Agent GNSS Measurement Collaboration Using Factor Graph Optimization for Smart Summon. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19471

conference

Zhang, Z., Penghui, Xu, Zhang, G., & Hsu, L.-T. (2023).Intelligent GNSS Satellite Visibility Classification in Urban Areas: A Deep Learning Approach with Interpretation. 2023 IEEE 26th International Conference on Intelligent Transportation Systems (ITSC). https://doi.org/10.1109/itsc57777.2023.10422660

conference

Bai, X.& Hsu, L.-T. (2023).GVIM: GNSS/Visual/IMU/Map Integration Via Sliding Window Factor Graph Optimization in Urban Canyons. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19458

conference

Runzhi, Hu, Wen, W., & Hsu, L.-T. (2023).Fisheye Camera Aided GNSS NLOS Detection and Learning-Based Pseudorange Bias Correction for Intelligent Vehicles in Urban Canyons. 2023 IEEE 26th International Conference on Intelligent Transportation Systems (ITSC). https://doi.org/10.1109/itsc57777.2023.10422540

conference

Zhang, G., Hai, Di, Hoi-Fung, Ng, & Hsu, L.-T. (2023).Extending 3DMA GNSS with Diffraction Features in Urban Areas: Feasibility Analysis and Preliminary Results. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19339

conference

Vicenzo, S., Bing, Xu, Dey, A., & Hsu, L.-T. (2023).Experimental Investigation of GNSS Direct Position Estimation in Densely Urban Area. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19341

conference

Penghui, Xu, Hoi-Fung, Ng, Zhong, Y., Zhang, G., Wen, W., Yang, Bo, & Hsu, L.-T. (2023).Differentiable Factor Graph Optimization with Intelligent Covariance Adaptation for Accurate Smartphone Positioning. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19297

conference

Huang, F., Wen, W., Zhang, G., Dongzhe, Su, & Hsu, L.-T. (2023).Adaptive Multi-Sensor Integrated Navigation System Aided by Continuous Error Map from RSU for Autonomous Vehicles in Urban Areas. 2023 IEEE 26th International Conference on Intelligent Transportation Systems (ITSC). https://doi.org/10.1109/itsc57777.2023.10422216

conference

Zhang, H., Wen, W., & Hsu, L.-T. (2023).A New GNSS Ambiguity Resolution Method Through Mixed Integer Programming. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19317

conference

Zhang, L., Hoi-Fung, Ng, Zhang, G., & Hsu, L.-T. (2023).3D Mapping Aided GNSS Positioning Using Doppler Frequency for Urban Areas. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19340

conference

Liu, X., Wen, W., & Hsu, L.-T. (2023).3D LiDAR Aided GNSS NLOS Correction with Direction of Arrival Estimation Using Doppler Measurements. Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023). https://doi.org/10.33012/2023.19447

2022 (11)

patent

Hsu, L. T& Wen, W (2022).3D LiDAR Aided GNSS and the Method for NLOS Detection and Correction (US 2023/0033404 A1). U.S. Patent and Trademark Office. https://patents.google.com/patent/US20230033404A1

patent

Meng, Q, Hsu, L. T, & B, X. (2022).Spoofing Signal Generation Method and Apparatus (欺骗信号生成方法及装置, granted) (ZL 201910778721.8). China National Intellectual Property Administration (CNIPA).

journal Q1

Wen, W., Zhang, G., & Hsu, L. T. (2022).GNSS Outlier Mitigation via Graduated Non-Convexity Factor Graph Optimization. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2021.3130909

journal Q1

Dey, A., Iyer, K., B., X., Sharma, N., & Hsu, L. T. (2022).Carrier-Aided Dual Frequency Vectorized Tracking Architecture for NavIC Signals. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2022.3146927

journal Q1

Bai, X., Wen, W., & Hsu, L. T. (2022).Time-correlated Window Carrier-phase Aided GNSS Positioning Using Factor Graph Optimization for Urban Positioning. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2022.3149730

journal Q2

Zhang, J, Wen, W, Huang, F, Wang, Y, Chen, X, & Hsu, L. T. (2022).GNSS-RTK Adaptively Integrated with LiDAR/IMU Odometry for Continuously Global Positioning in Urban Canyons. Applied Sciences. https://doi.org/10.3390/app12105193

journal Q1

Wen, W. and Hsu L.-T. (2022).3D LiDAR Aided GNSS NLOS Mitigation in Urban Canyons. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2022.3167710

journal Q1

Meng, Q. and Hsu L. T. (2022).Resilient Interactive Sensor-Independent-Update Fusion Navigation Method. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2022.3150273

journal Q1

Jia, Q., Hsu, & L. T. and Wu, R. (2022).Scalar and vector tracking loop simulation based on a uniform semi-analytic model and robustness analysis in multipath/NLOS situations. GPS Solutions. https://doi.org/10.1007/s10291-022-01280-w

journal Q1

Yue, J.& Xu B. and Hsu, L. T. (2022).Data Denoising Based on Hadamard Matrix Transformation and Rayleigh Quotient Maximization: Application to GNSS Signal Classification. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2022.3184357

conference

Liu, X., Wen, W., & Hsu, L.-T. (2022).3D LiDAR Aided GNSS Real-time Kinematic Positioning via Coarse-to-fine Batch Optimization for High Accuracy Mapping in Dense Urban Canyons. Proceedings of the 35th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2022). https://doi.org/10.33012/2022.18545

2021 (12)

patent

Zhang, G& Hsu, L. T (2021).3D map-aided GNSS cooperative positioning method and system (ZL 201910866398.X). China National Intellectual Property Administration. https://patents.google.com/patent/CN110426717B

journal Q1

Jiang, C., B., X., & Hsu, L. T. (2021).A Probabilistic Approach to Detect and Mitigate GNSS NLOS Using State Augmented Kalman Filter. GPS Solutions. https://doi.org/10.1007/s10291-021-01101-6

journal Q1

Zhang, G.& Hsu, L. T. (2021).Performance Assessment of the GNSS Diffraction Models in Urban Areas. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.1002/navi.417

journal Q1

Zhang, G., B., X., H.F., N., & Hsu, L. T. (2021).GNSS RUMS: GNSS Realistic Urban Multi-agent Simulator for Collaborative Positioning Research. Remote Sensing. https://doi.org/10.20944/preprints202012.0647.v1

journal Q1 Featured

Wen, W., Pfeifer, T., Bai, X., & Hsu, L. T. (2021).Factor Graph Optimization for GNSS/INS Integration: A Comparison with the Extended Kalman Filter. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.1002/navi.421

journal Q1 Featured

H.F., N., Zhang, G., & Hsu, L. T. (2021).Robust GNSS Shadow Matching for Smartphones in Urban Canyons. IEEE Sensors Journal. https://doi.org/10.1109/jsen.2021.3083801

journal Q1

H.F., N., Zhang, G., & Hsu, L. T. (2021).Urban Positioning: 3D Mapping Aided GNSS using Dual-Frequency Pseudorange Measurements from Smartphones. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.1002/navi.448

journal Q1

Zhang, J., Wen, W., Huang, F., & Hsu, L. T. (2021).Coarse-to-Fine Loosely-Coupled LiDAR-Inertial Odometry for Urban Positioning and Mapping. Remote Sensing. https://doi.org/10.3390/rs13122371

journal Q1

Zhang, G., P., X., H., X., & Hsu, L. T. (2021).Prediction on the Urban GNSS Measurement Uncertainty based on Deep Learning Networks with Long Short-Term Memory. IEEE Sensors Journal. https://doi.org/10.1109/jsen.2021.3098006

journal Q1

Yue, J., Wen, W., Han, J., & Hsu, L. T. (2021).3D Point Clouds Data Super Resolution Aided LiDAR Odometry for Vehicular Positioning in Urban Canyons. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2021.3069212

journal Q1 Featured

H.F., N.& Hsu, L.T. (2021).3D Mapping Database Aided GNSS RTK and Its Assessments in Urban Canyons. IEEE Transactions on Aerospace and Electronic Systems. https://doi.org/10.1109/taes.2021.3069271

journal Q2

Lee, J.L. M., Hsu, L. T., & H.-F., N. (2021).Semantic-Based VPS for Smartphone Localization in Challenging Urban Environments. Sensors. https://doi.org/10.3390/s21186137

2020 (19)

journal Q1

H., X., Angrisano, A., Gaglione, S., & Hsu, L. T. (2020).Machine Learning based LOS/NLOS Classifier and Robust Estimator for GNSS Shadow Matching. Satellite Navigation. https://doi.org/10.1186/s43020-020-00016-w

journal Q3

El-Mowafy, A., B., X., & Hsu, L. T. (2020).Integrity Monitoring of multi-GNSS SPP and DGNSS in Urban Environment using ARAIM and 3D City Models. Journal of Spatial Science.

journal Q3

Meng, Q.& Hsu, L. T. (2020).Integrity for Autonomous Vehicles and Towards a Novel Alert Limit Determination Method. Proc. IMechE, Part D: Journal of Automobile Engineering. https://doi.org/10.1177/0954407020965760

journal Q3

Bai, X., Wen, W., & Hsu, L. T. (2020).Using Sky-Pointing Fish-eye Camera and LiDAR to Aid GNSS Single Point Positioning in Urban Canyons. IET Intelligent Transport Systems. https://doi.org/10.1049/iet-its.2019.0587

journal Q1

H., X., Hsu, L. T., D., L., & Cai, B. (2020).Sky Visibility Estimation based on GNSS Satellite Visibility: An Approach of GNSS based Context-Awareness. GPS Solutions. https://doi.org/10.1007/s10291-020-0973-5

journal Q1

Chiang, K. W., H., L. Y., Hsu, L. T., & Chu, F. Y. (2020).The Design a TDCP-Smoothed GNSS/Odometer Integration Scheme with Vehicular-Motion Constraint and Robust Regression. Remote Sensing. https://doi.org/10.3390/rs12162550

journal Q1

Bai, X., Wen, W., & Hsu, L. T. (2020).Robust Visual-Inertial Integrated Navigation System Aided by Online Sensor Model Adaption for Autonomous Ground Vehicles in Urban Areas. Remote Sensing. https://doi.org/10.20944/preprints202003.0018.v1

journal Q1

Wen, W., Zhang, G., & Hsu, L. T. (2020).Object Detection Aided GNSS and Its Integration with LiDAR in Highly Urbanized Areas. IEEE Intelligent Transportation Systems Magazine. https://doi.org/10.1109/mits.2020.2994131

journal Q1

Meng, Q.& Hsu, L. T. (2020).Integrity Monitoring for All-Source Navigation Enhanced by Kalman Filter-Based Solution Separation. IEEE Sensors Journals. https://doi.org/10.1109/jsen.2020.3026081

journal Q1

Sun, R., L., F., Wang, G, Cheng, Q., & Hsu, L. T. and Ochieng W. Y. (2020).Using Dual-Polarization GPS Antenna with Optimized Adaptive Neuro-Fuzzy Inference System to Improve Single Point Positioning Accuracy in Urban Canyons. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.1002/navi.408

journal Q1

F., N. H., Zhang, G., & Hsu, L. T. (2020).A Computation Effective Range-Based 3D Mapping Aided GNSS with NLOS Correction Method. Journal of Navigation. https://doi.org/10.1017/s037346332000003x

journal Q2

Wen, W., Bai, X., Zhang, G., Chen, S., Yuan, F., & Hsu, L. T. (2020).Multi-Agent Collaborative GNSS/Camera/INS Integration Aided by Inter-ranging for Vehicular Navigation in Urban Areas. IEEE Access. https://doi.org/10.1109/access.2020.3006210

journal Q2

H.F., N., Zhang, G., Yang, K.Y., & Yang, S. X. Hsu L. T. (2020).Improved Weighting Scheme using Consumer-level GNSS L5/E5a/B2a Pseudorange Measurements in the Urban Area. Advances in Space Research. https://doi.org/10.1016/j.asr.2020.06.002

journal Q2

Lee, M.J.L., Lee, S., F., N. H., & Hsu, L T. (2020).Skymask Matching Aided Positioning Using Sky-Pointing Fisheye Camera and 3D City Models in Urban Canyons. Sensors. https://doi.org/10.3390/s20174728

journal Q1

Zhang, G., Wen, W. Xu B., & Hsu, L. T. (2020).Extending Shadow Matching to Tightly-Coupled GNSS/INS Integration System. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2020.2981093

journal Q1

Zhang, G., F., N. H., & Hsu, L. T. (2020).3D Mapping Database Aided GNSS Based Collaborative Positioning Using Factor Graph Optimization. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2020.2988531

journal Q1

Jia, Q., Hsu, L. T., B., X., & R., W. (2020).Assessment of beamforming for GNSS multipath mitigation with a cost-effective structure. Journal of Navigation.

journal Q1

Sun, R., Wang, G., Cheng, Q., L., F., Chiang, K.W., & Hsu, L. T. and Ochieng W. Y. (2020).Improving GPS Code Phase Positioning Accuracy in Urban Environments Using Machine Learning. IEEE Internet of Things Journal. https://doi.org/10.1109/jiot.2020.3037074

magazine

Hsu, L. T (2020).What are the roles of artificial intelligence and machine learning in GNSS positioning. Inside GNSS.

2019 (12)

book

Hsu, L. T., Wen, W., & Zhang, G (2019).Chapter 2 - Vehicular Positioning System. Nova Science Publishers Inc.

journal Q1

B., X.& Hsu, L. T. (2019).An Open Source Matlab Code on GPS Vector Tracking based on Software-Defined Receiver. GPS Solutions. https://doi.org/10.1007/s10291-019-0839-x

journal Q1

Luo, Y., J., L., C., Y., B., X., Y., L., Hsu, L. T., & El-Sheimy, N. (2019).Research on Time-Correlated Errors Using Allan Variance in a Kalman Filter Applicable to Vector-Tracking-Based GNSS Software-Defined Receiver for Autonomous Ground Vehicle Navigation. Remote Sensing. https://doi.org/10.3390/rs11091026

journal Q1

Zhang, G., Wen, W., & Hsu, L. T. (2019).Rectification of GNSS based Collaborative Positioning using 3D Building Models in Urban Areas. GPS Solutions. https://doi.org/10.1007/s10291-019-0872-9

journal Q1

B., X., Jia, Q., Luo, Y., & Hsu, L. T. (2019).Intelligent GPS L1 LOS/Multipath/NLOS Classifiers Based on Correlator-, RINEX-and NMEA-Level Measurements. Remote Sensing. https://doi.org/10.3390/rs11161851

journal Q1

Wen, W., Zhang, G., & Hsu, L. T. (2019).Correcting NLOS by 3D LiDAR and building height to improve GNSS single point positioning. NAVIGATION: Journal of the Institute of Navigation. https://doi.org/10.1002/navi.335

journal Q1

Sun, R., Hsu, L. T., Xue, D., Zhang, G., & Washington, Y.O. (2019).GPS Signal Reception Classification Using Adaptive Neuro-Fuzzy Inference System. Journal of Navigation. https://doi.org/10.1017/s0373463318000899

journal Q1

Wen, W., Bai, X., Kan, Y.C., & Hsu, L. T. (2019).Tightly Coupled GNSS/INS Integration Via Factor Graph and Aided by Fish-eye Camera. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2019.2944680

journal Q1

B., X.& Jia, Q. and Hsu L. T. (2019).Vector Tracking Loop-based GNSS NLOS Detection and Correction: Algorithm Design and Performance Analysis. IEEE Transactions on Instrumentation and Measurement. https://doi.org/10.1109/tim.2019.2950578

journal Q1

Sun, R., Wang, G., Zhang, W., & Hsu, L. T. and Ochieng W. Y. (2019).A Gradient Boosting Decision Tree Based GPS Signal Reception Classification Algorithm. Applied Soft Computing Journal. https://doi.org/10.1016/j.asoc.2019.105942

journal Q1

Wen, W., Zhang, G., & Hsu, L. T. (2019).GNSS NLOS Exclusion Based on Dynamic Object Detection Using LiDAR Point Cloud. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2019.2961128

magazine

Wen, W& Hsu, L. T (2019).Perceived Environment Aided GNSS Single Point Positioning: An Example using LiDAR Scanner. Inside GNSS.

2018 (5)

patent

Wang, Y& Hsu, L. T (2018).Positioning method and electronic equipment (CN 111198389B). China National Intellectual Property Administration. https://patents.google.com/patent/CN111198389B

journal Q2

Y., G., Hsu, L.T., & Kamijo, S. (2018).Towards lane-level traffic monitoring in urban environment using precise probe vehicle data derived from three-dimensional map aided differential GNSS. IATSS Research. https://doi.org/10.1016/j.iatssr.2018.03.001

journal Q4

Huang, Y., Y., G., & Hsu, L. T. (2018).GNSS Correction using Altitude Map and Its Integration with Pedestrian Dead Reckoning. IEICE Transactions on Fundamentals of Electronics, Communications and Computer Science. https://doi.org/10.1587/transfun.e101.a.1245

journal Q1

Hsu, L. T. (2018).Analysis and Modelling GPS NLOS effect in Highly Urbanized Area. GPS Solutions. https://doi.org/10.1007/s10291-017-0667-9

journal Q1

Zhang, G.& Hsu, L. T. (2018).Intelligent GNSS/INS Integrated Navigation System for a Commercial UAV Flight Control System. Aerospace Science and Technology. https://doi.org/10.1016/j.ast.2018.07.026

2017 (3)

journal unranked

Kubo, N., Kobayashi, K., Hsu, L.T., & Amai, O. (2017).Multipath Mitigation Technique under Strong Multipath Environment Using Multiple Antennas. Journal of Aeronautics, Astronautics and Aviation, Series A.

journal Q1

Hsu, L.T., Y., G., & Kamijo, S. (2017).Intelligent Viaduct Recognition and Driving Altitude Determination using GPS Data. IEEE Transactions on Intelligent Vehicles. https://doi.org/10.1109/tiv.2017.2737325

journal Q1

Hsu, L. T., Tokura, H., Kubo, N., Y., G., & Kamijo, S. (2017).Multiple Faulty GNSS Measurement Exclusion based on Consistency Check in Urban Canyons. IEEE Sensors Journal. https://doi.org/10.1109/jsen.2017.2654359

2016 (5)

journal Q3

Y., G., Hsu, L. T., Bao, J., & Kamijo, S. (2016).Integrating Global Navigation Satellite System and Road-Marking Detection for Vehicle Localization in Urban Traffic. Transportation Research Record Journal. https://doi.org/10.3141/2595-07

journal Q1

Hsu, L. T., Y., G., & Kamijo, S. (2016).3D Building Model Pedestrian Positioning Method using GPS/GLONASS/QZSS and Its Reliability Calculation. GPS Solutions. https://doi.org/10.1007/s10291-015-0451-7

journal Q1

Hsu, L. T., Y., G., Huang, Y., & Kamijo, S. (2016).Urban Pedestrian Navigation using Smartphone-based Dead Reckoning and 3D Maps Aided GNSS. IEEE Sensors Journal. https://doi.org/10.1109/jsen.2015.2496621

journal Q1

Wada, Y., Hsu, L. T., Y., G., & Kamijo, S. (2016).Optimization of 3D Building Models by GPS Measurements. GPS Solutions. https://doi.org/10.1007/s10291-015-0504-y

journal Q1

Y., G., Hsu, L. T., & Kamijo, S. (2016).GNSS/On-Board Inertial Sensor Integration with the Aid of 3D Building Map for Lane-Level Vehicle Self-Localization in Urban Canyon. IEEE Transactions on Vehicular Technology. https://doi.org/10.1109/tvt.2015.2497001

2015 (6)

journal Q4

Hsu, L. T., Chen, F., & Kamijo, S. (2015).Evaluation of Multi-GNSSs and GPS with 3D Map Methods for Pedestrian Positioning in an Urban Canyon Environment. IEICE Transactions. https://doi.org/10.1587/transfun.e98.a.284

journal Q1

Miura, S., Hsu, L. T., Chen, F., & Kamijo, S. (2015).GPS Error Correction with Pseudorange Evaluation Using 3-dimensional Maps. IEEE Transactions on Intelligent Transportation Systems. https://doi.org/10.1109/tits.2015.2432122

journal Q2

Y., G., Hsu, L. T, & Kamijo, S. (2015).Passive Sensor Integration for Vehicle Self-Localization in Urban Traffic Environment. Sensors. https://doi.org/10.3390/s151229795

journal Q2

Hsu, L. T., Y., G., & Kamijo, S. (2015).NLOS Correction/Exclusion for GNSS Measurement using RAIM and City Building Models. Sensors. https://doi.org/10.3390/s150717329

magazine

Hsu, L. T, Miura, S, & Kamijo, S (2015).Street Smart: 3-D City Mapping and Modeling for Positioning with Multi-GNSS. GPS World.

magazine

Kamijo, S, Y, G., & Hsu, L. T (2015).Autonomous Vehicle Technologies: Localization and Mapping. IEICE Fundamentals Review. https://doi.org/10.1587/essfr.9.2_131

2014 (1)

journal Q1

Hsu, L. T., Jan, S. S., Groves, P. D., & Kubo, N. (2014).Multipath mitigation and NLOS detection using vector tracking in urban. GPS Solutions. https://doi.org/10.1007/s10291-014-0384-6

2013 (1)

journal unranked

Hsu, L. T.& Jan, S. S. (2013).Performance Analysis of Advanced GPS Receiver Technique in Radio Frequency Difficult Environment. Journal of Aeronautics, Astronautics and Aviation, Series A.

2010 (1)

journal unranked

Jan, S. S.& Hsu, L. T. (2010).Assessment of Composite PRN Code Acquisition Methods for GPS Signal. Journal of the Chinese Society of Mechanical Engineers.

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