563 research outputs found
Indoor positioning with deep learning for mobile IoT systems
2022 Summer.Includes bibliographical references.The development of human-centric services with mobile devices in the era of the Internet of Things (IoT) has opened the possibility of merging indoor positioning technologies with various mobile applications to deliver stable and responsive indoor navigation and localization functionalities that can enhance user experience within increasingly complex indoor environments. But as GPS signals cannot easily penetrate modern building structures, it is challenging to build reliable indoor positioning systems (IPS). Currently, Wi-Fi sensing based indoor localization techniques are gaining in popularity as a means to build accurate IPS, benefiting from the prevalence of 802.11 family. Wi-Fi fingerprinting based indoor localization has shown remarkable performance over geometric mapping in complex indoor environments by taking advantage of pattern matching techniques. Today, the two main information extracted from Wi-Fi signals to form fingerprints are Received Signal Strength Index (RSSI) and Channel State Information (CSI) with Orthogonal Frequency-Division Multiplexing (OFDM) modulation, where the former can provide the average localization error around or under 10 meters but has low hardware and software requirements, while the latter has a higher chance to estimate locations with ultra-low distance errors but demands more resources from chipsets, firmware/software environments, etc. This thesis makes two novel contributions towards realizing viable IPS on mobile devices using RSSI and CSI information, and deep machine learning based fingerprinting. Due to the larger quantity of data and more sophisticated signal patterns to create fingerprints in complex indoor environments, conventional machine learning algorithms that need carefully engineered features suffer from the challenges of identifying features from very high dimensional data. Hence, the abilities of approximation functions generated from conventional machine learning models to estimate locations are limited. Deep machine learning based approaches can overcome these challenges to realize scalable feature pattern matching approaches such as fingerprinting. However, deep machine learning models generally require considerable memory footprint, and this creates a significant issue on resource-constrained devices such as mobile IoT devices, wearables, smartphones, etc. Developing efficient deep learning models is a critical factor to lower energy consumption for resource intensive mobile IoT devices and accelerate inference time. To address this issue, our first contribution proposes the CHISEL framework, which is a Wi-Fi RSSI- based IPS that incorporates data augmentation and compression-aware two-dimensional convolutional neural networks (2D CAECNNs) with different pruning and quantization options. The proposed model compression techniques help reduce model deployment overheads in the IPS. Unlike RSSI, CSI takes advantages of multipath signals to potentially help indoor localization algorithms achieve a higher level of localization accuracy. The compensations for magnitude attenuation and phase shifting during wireless propagation generate different patterns that can be utilized to define the uniqueness of different locations of signal reception. However, all prior work in this domain constrains the experimental space to relatively small-sized and rectangular rooms where the complexity of building interiors and dynamic noise from human activities, etc., are seldom considered. As part of our second contribution, we propose an end-to-end deep learning based framework called CSILoc for Wi-Fi CSI-based IPS on mobile IoT devices. The framework includes CSI data collection, clustering, denoising, calibration and classification, and is the first study to verify the feasibility to use CSI for floor level indoor localization with minimal knowledge of Wi-Fi access points (APs), thus avoiding security concerns during the offline data collection process
A survey of deep learning approaches for WiFi-based indoor positioning
One of the most popular approaches for indoor positioning is WiFi fingerprinting, which has been intrinsically tackled as a traditional machine learning problem since the beginning, to achieve a few metres of accuracy on average. In recent years, deep learning has emerged as an alternative approach, with a large number of publications reporting sub-metre positioning accuracy. Therefore, this survey presents a timely, comprehensive review of the most interesting deep learning methods being used for WiFi fingerprinting. In doing so, we aim to identify the most efficient neural networks, under a variety of positioning evaluation metrics for different readers. We will demonstrate that despite the new emerging WiFi signal measures (i.e. CSI and RTT), RSS produces competitive performances under deep learning. We will also show that simple neural networks outperform more complex ones in certain environments
Redundant and Loosely Coupled LiDAR-Wi-Fi Integration for Robust Global Localization in Autonomous Mobile Robotics
This paper presents a framework addressing the challenge of global
localization in autonomous mobile robotics by integrating LiDAR-based
descriptors and Wi-Fi fingerprinting in a pre-mapped environment. This is
motivated by the increasing demand for reliable localization in complex
scenarios, such as urban areas or underground mines, requiring robust systems
able to overcome limitations faced by traditional Global Navigation Satellite
System (GNSS)-based localization methods. By leveraging the complementary
strengths of LiDAR and Wi-Fi sensors used to generate predictions and evaluate
the confidence of each prediction as an indicator of potential degradation, we
propose a redundancy-based approach that enhances the system's overall
robustness and accuracy. The proposed framework allows independent operation of
the LiDAR and Wi-Fi sensors, ensuring system redundancy. By combining the
predictions while considering their confidence levels, we achieve enhanced and
consistent performance in localization tasks.Comment: 7 pages, 5 figures. Accepted for publication in the 21st
International Conference on Advanced Robotics (ICAR 2023
FedHIL: Heterogeneity Resilient Federated Learning for Robust Indoor Localization with Mobile Devices
Indoor localization plays a vital role in applications such as emergency
response, warehouse management, and augmented reality experiences. By deploying
machine learning (ML) based indoor localization frameworks on their mobile
devices, users can localize themselves in a variety of indoor and subterranean
environments. However, achieving accurate indoor localization can be
challenging due to heterogeneity in the hardware and software stacks of mobile
devices, which can result in inconsistent and inaccurate location estimates.
Traditional ML models also heavily rely on initial training data, making them
vulnerable to degradation in performance with dynamic changes across indoor
environments. To address the challenges due to device heterogeneity and lack of
adaptivity, we propose a novel embedded ML framework called FedHIL. Our
framework combines indoor localization and federated learning (FL) to improve
indoor localization accuracy in device-heterogeneous environments while also
preserving user data privacy. FedHIL integrates a domain-specific selective
weight adjustment approach to preserve the ML model's performance for indoor
localization during FL, even in the presence of extremely noisy data.
Experimental evaluations in diverse real-world indoor environments and with
heterogeneous mobile devices show that FedHIL outperforms state-of-the-art FL
and non-FL indoor localization frameworks. FedHIL is able to achieve 1.62x
better localization accuracy on average than the best performing FL-based
indoor localization framework from prior work
Indoor navigation systems based on data mining techniques in internet of things: a survey
© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Internet of Things (IoT) is turning into an essential part of daily life, and numerous IoT-based scenarios will be seen in future of modern cities ranging from small indoor situations to huge outdoor environments. In this era, navigation continues to be a crucial element in both outdoor and indoor environments, and many solutions have been provided in both cases. On the other side, recent smart objects have produced a substantial amount of various data which demands sophisticated data mining solutions to cope with them. This paper presents a detailed review of previous studies on using data mining techniques in indoor navigation systems for the loT scenarios. We aim to understand what type of navigation problems exist in different IoT scenarios with a focus on indoor environments and later on we investigate how data mining solutions can provide solutions on those challenges
Sensors and Systems for Indoor Positioning
This reprint is a reprint of the articles that appeared in Sensors' (MDPI) Special Issue on “Sensors and Systems for Indoor Positioning". The published original contributions focused on systems and technologies to enable indoor applications
- …