Indoor and Outdoor Localization Technologies

Latest papers

• AirLog: Store-Level Indoor Life Logging Made Easy

  Zihui Yun, Jiaying Du, Yue Yu, Zhewei Liu, Zhen Xiang, Longfei Shangguan, Zhenlin An · 29 September 2026

  This paper presents AirLog, a smartphone-based life journaling system that automatically reconstructs users' store visits in shopping malls and summarizes them into human-readable journals. Unlike conventional indoor localization systems, AirLog avoids labor-intensive radio-map construction and dedi…

• Interpretable Physics Informed WiFi Indoor Localization: Learning an Effective Access Point Geometry and Using It to Prune

  Arshia Eftekhari zadeh, Rezvan Nasiri, Hadi Moradi · 29 September 2026

  Deep learning models can achieve high accuracy for indoor localization, but their black-box nature limits interpretability and the reuse of learned information. We propose a hierarchical deep learning framework for WiFi fingerprint-based indoor localization that jointly predicts user location and le…

• CSI-Agent: LLM-Assisted Few-Shot Adaptation for Cross-Domain Wi-Fi CSI Sensing

  Tianya Zhao, Chuan Liu, Xuyu Wang · 29 September 2026

  Wi-Fi channel state information (CSI) has enabled device-free sensing applications such as human activity recognition. However, CSI sensing models remain brittle in cross-domain deployment, where changes in users or environments can produce incorrect predictions. Existing solutions usually treat thi…

• Structured Pose-Conditioned Flow Matching for Generative 5G CSI Augmentation

  Haojin Li, Anbang Zhang, Wai Ho Mow, Chenyuan Feng, Chen Sun, Haijun Zhang · 25 September 2026

  With the growing demand for privacy-preserving and occlusion-resilient human pose recognition (HPR), 5G channel state information (CSI) offers a promising contactless sensing modality by integrating communication and sensing capabilities. However, collecting large-scale synchronized CSI-pose pairs r…

• Untangling the Geometry and Speed for RF Sensing Spectrograms

  Mert Torun, Darius Cuenca, Yasamin Mostofi · 24 September 2026

  A fundamental challenge in RF sensing is that Doppler signatures observed by a link entangle the target's motion with the sensing geometry, resulting in limited applicability to unconstrained real-world settings. In this paper, we establish a new foundation for physically interpretable RF sensing th…

• Bridging the Data Gap: Digital Twin as a New Paradigm for AI-based Radio Sensing

  \'Eloi Sainte-Beuve (Orange Research), Guillaume Larue (Orange Research), Louis-Adrien Dufr\`ene (Orange Research), Quentin Lampin (Orange Research), Ali Al Khansa (Orange Research) · 23 September 2026

  We present a methodology that places a 3D digital twin (DT) of the environment as the main enabler behind the development of radio sensing at scale. The DT acts as a world model, providing geometry, materials, and transmitter/receiver placements to a ray-tracing engine that generates time-indexed ch…

• Radiance-Field Guided Pretraining: Scaling Localization Models with Unlabeled Wireless Signals

  Guosheng Wang, Shen Wang, Lei Yang · 23 September 2026

  Radio frequency (RF)-based indoor localization offers significant promise for applications such as indoor navigation, augmented reality, and pervasive computing. While deep learning has greatly enhanced localization accuracy and robustness, existing localization models still face major challenges in…

• CIG-MAE: Cross-Modal Information-Guided Masked Autoencoder for Self-Supervised WiFi Sensing

  Gang Liu, Yanling Hao, Yixuan Zou · 22 September 2026

  Human Action Recognition using WiFi Channel State Information (CSI) has emerged as an attractive alternative to vision-based methods due to its ubiquity, device-agnostic nature, and inherent privacy-preserving capabilities. However, the high cost of manual annotation and the limited scale of publicl…

• Vision-Wireless Fusion for Multi-User Localization: A Cross-Modal Transformer Approach

  Can Zheng, Jiguang He, Guofa Cai, Henk Wymeersch, Merouane Debbah · 22 September 2026

  Accurate multi-user localization is challenging in complex urban environments, where wireless measurements can become ambiguous under noise, blockage, and multipath, while visual observations provide complementary spatial context. This paper presents a vision-wireless fusion framework for multi-user…

• Cross-Domain Inference for Human Localization: Applying Wi-Fi RSSI Data to CSI-Trained Models

  Ariel Duschanek-Myers, Thomas Welsh, Helmut Neukirchen · 16 September 2026

  Wi-Fi signal data can be used to compromise the privacy of individuals. While many existing approaches rely on Channel State Information (CSI), collecting this data on typical IoT devices often requires elevated operating system permissions and specialized drivers. Consequently, this paper investiga…

• Reliable Near-Field Multi-User Positioning Informed by Two-Stage MUSIC

  Jiaying Li, Haifeng Wen, Changsheng You, Yuanwei Liu, Hong Xing · 10 September 2026

  Near-field localization is a promising technique for high-resolution multi-user positioning in future wireless systems, but its performance is often degraded by scattering-induced coherent propagation. Existing near-field localization methods, which require separate parameter estimation and path/sou…

• A Deep Generative Model for Synthesizing Labeled Wireless Signals

  Yuxiao Li, Keke Hu, Santiago Mazuelas, Yuan Shen · 7 September 2026

  Wireless signals with position-related labels are pivotal for both performance evaluation and model training in the realm of wireless sensing. However, acquiring real-world datasets is often challenged by significant measurement and labeling costs. Traditional methods for synthesizing labeled wirele…

• A comparison between ceiling-mounted FMCW, IR-UWB and Wi-Fi radar for in-bedroom human activity monitoring and sleep interruption detection

  Anton Lambrecht, Reda El Hail, Xianjun Jiao, Pieter Crombez, Dominique Schreurs, Peter Karsmakers, Adnan Shahid, Eli De Poorter · 21 August 2026

  Despite their growing importance for contact-free radio frequency (RF) based healthcare monitoring, different radio technologies such as frequency-modulated continuous wave (FMCW) radar, impulse radio ultra-wideband (IR-UWB), and Wi-Fi sensing are rarely compared under identical deployment condition…

• Learnware for CSI Feedback: Scene-specific Small Models Can Do Big

  Xiangyi Li, Jiajia Guo, Chao-Kai Wen, Xin Geng, Shi Jin, Zhi-Hua Zhou · 19 August 2026

  Intelligent channel state information (CSI) feedback is essential for realizing the high capacity and spectral efficiency goals of future 6G systems, yet existing deep learning solutions face a trade-off between model generalization and scenario-specific performance. Large neural networks generalize…

• KOALA: Koopman Operator Learning for WiFi-Based Anticipatory Hum

  Quang-Anh N. D., Duc Pham Minh, Thao Phuong Pham, Minh Anh Nguyen, Huan X. Nguyen, Tuan Dang · 18 August 2026

  WiFi Channel State Information (CSI) has emerged as a privacy-preserving alternative to cameras for human pose estimation. However, existing approaches treat pose inference as an instantaneous regression problem and do not model temporal dynamics, making future motion prediction infeasible. Naively …

• ARGUS: Attention-Guided Transformers for Scalable Person Identification Using Wi-Fi Telemetry

  Nayan Sanjay Bhatia, Pranay Kocheta, Yuhan Li, Katia Obraczka · 18 August 2026

  Passive, device-free person identification offers an alternative to camera- and wearable-based biometrics, yet existing wireless approaches rely largely on gait or activity cues and are rarely evaluated at scale. In this paper, we present \emph{Argus}, a passive Wi-Fi sensing system that identifies …

• ControlRadio: Prompt-Driven Controllable Diffusion for Cross-Modal Radio Map Generation

  Kangjun Liu, Xiying Pan, Shuhang Zhang, Xiang Xiang, Ke Chen, Yaowei Wang · 11 August 2026

  Radio maps describe how wireless signals propagate across space and are essential for wireless communication, sensing, and network planning. However, constructing accurate radio maps traditionally requires either dense measurements or computationally expensive physical simulations, which limits scal…

• DoRF++: Spherical Representation Learning over Doppler Radiance Fields for Robust Wi-Fi Sensing

  Navid Hasanzadeh, Shahrokh Valaee · 11 August 2026

  Motivated by the IEEE 802.11bf effort to standardize advanced WLAN sensing, interest in Wi-Fi Channel State Information (CSI) for passive, device-free, and privacy-preserving activity and gesture recognition has grown rapidly. Recent studies have shown that Doppler velocity projections extracted fro…

• Vision Meets WiFi: Physics-Grounded Estimation of Volumetric Mechanical Properties

  Ali Bahri, Hongliang Li, Soufiane Lamghari, Jie Chuai, Zhitang Chen · 11 August 2026

  Estimating volumetric mechanical properties, including Young's modulus, Poisson's ratio, and density at each voxel, is intrinsically ambiguous from vision alone, as visually similar objects may have substantially different material compositions and physical behavior. Existing approaches predict thes…

• GLocFM: A Geometry-Aware Foundation Model for 3D Indoor Wireless Localization

  Chenghong Bian, Chaozheng Wen, Hongze Chen, Jun Zhang · 11 August 2026

  Learning-based wireless localizers often fail to utilize geometric information about the propagation environment, limiting their ability to exploit non-line-of-sight (NLoS) propagation and generalize across scenes. To bridge this gap, we propose GLocFM, a Geometry-aware Localization Foundation Model…

• FSTC-Encoder: Feature--Spatial--Temporal Correlation Learning for Generalizable RF Sensing

  Jing Wang, Zhu Wang, Changlong Cheng, Yifan Guo, Yin Zhang · 11 August 2026

  Heterogeneous RF sensing differs substantially in feature structure, spatial layout, and temporal scale, making existing models difficult to reuse across devices, environments, and RF modalities. We propose FSTC-Encoder, which unifies heterogeneous RF representation learning through feature, spatial…

• Decentralized Indoor Localization Based on A Sparse Gaussian Process with Reduced-Dimensional Inputs for Real-Time Sensing and Training on IoT Devices

  Zhe Tang, Sihao Li, Zichen Huang, Guandong Yang, Kyeong Soo Kim, Jeremy S. Smith, Zhaowei Zhu, Qi Xuan · 10 August 2026

  As a large number of Internet of Things (IoT) devices are deployed in the field, there arises huge potential of edge computing for indoor localization on those devices. Conventional indoor localization based on a centralized server with substantial computational resources, often covering a number of…

• RIS-Aided mmWave Localization Under Cross-Link Interference via Beam-Domain ML Fingerprinting

  Md Tarek Hassan, Dmitry Zelenchuk, Muhammad Ali Babar Abbasi · 10 August 2026

  Accurate user equipment (UE) localization is critical for beam management in reconfigurable intelligent surface (RIS)-assisted millimeter-wave (mmWave) based sixth-generation (6G) networks, especially if the direct base-station-UE links are unavailable. This paper proposes a beam-domain fingerprint …

• Dual-Attention and Adversarial Transfer Networks for Sim-to-Real Cross-Orientation Wireless Sensing

  Linfeng Du, Kehan Wu, Tong Zhang, Rui Wang · 7 August 2026

  Millimeter-wave human activity recognition suffers significant performance degradation when the user's orientation changes relative to the sensing system, yet collecting labeled multi-orientation data is labor-intensive and costly. To eliminate the need for exhaustive multi-orientation measured data…

• A 6G Integrated Sensing and Communication Framework for Railway Intrusion Detection and Collision Prediction

  Ajeet Kumar Yadav, Sankaran Balasubramaniam, Aritra Chatterjee, Vinod Aduru, Yogesh Simmhan, Pandarasamy Arjunan · 6 August 2026

  Integrated Sensing and Communication (ISAC) combines sensing and communication to efficiently utilize wireless resources and is emerging as a key paradigm for next-generation wireless networks. By leveraging the wide bandwidth, high frequencies, and massive antenna arrays of 5G-Advanced and 6G syste…