LANDMARC: indoor location sensing using active RFID,” (2003)

by L M Ni, Y Liu, Y C Lau, A P Patil
Venue:in Proceedings of the First IEEE International Conference on Pervasive Computing and Communications,
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Wireless Sensor Network Localization Techniques

by Guoqiang Mao, Barıs Fidan, Brian D. O. Anderson
"... Wireless sensor network localization is an important area that attracted significant research interest. This interest is expected to grow further with the proliferation of wireless sensor network applications. This paper provides an overview of the measurement techniques in sensor network localizat ..."
Abstract - Cited by 209 (5 self) - Add to MetaCart
Wireless sensor network localization is an important area that attracted significant research interest. This interest is expected to grow further with the proliferation of wireless sensor network applications. This paper provides an overview of the measurement techniques in sensor network localization and the one-hop localization algorithms based on these measurements. A detailed investigation on multihop connectivity-based and distance-based localization algorithms are presented. A list of open research problems in the area of distance-based sensor network localization is provided with discussion on possible approaches to them.

Indoor localization without the pain

by Krishna Chintalapudi, Anand Padmanabha Iyer, Venkata N. Padmanabhan - In Proc. ACM MobiCom Conference , 2010
"... While WiFi-based indoor localization is attractive, the need for a significant degree of pre-deployment effort is a key challenge. In this paper, we ask the question: can we perform indoor localization with no pre-deployment effort? Our setting is an indoor space, such as an office building or a mal ..."
Abstract - Cited by 102 (0 self) - Add to MetaCart
While WiFi-based indoor localization is attractive, the need for a significant degree of pre-deployment effort is a key challenge. In this paper, we ask the question: can we perform indoor localization with no pre-deployment effort? Our setting is an indoor space, such as an office building or a mall, with WiFi coverage but where we do not assume knowledge of the physical layout, including the placement of the APs. Users carrying WiFi-enabled devices such as smartphones traverse this space in normal course. The mobile devices record Received Signal Strength (RSS) measurements corresponding to APs in their view at various (unknown) locations and report these to a localization server. Occasionally, a mobile device will also obtain and report a location fix, say by obtaining a GPS lock at the entrance or near a window. The centerpiece of our work is the EZ Localization algorithm, which runs on the localization server. The key intuition is that all of the observations reported to the server, even the many from unknown locations, are constrained by the physics of wireless propagation. EZ models these constraints and then uses a genetic algorithm to solve them. The results from our deployment in two different buildings are promising. Despite the absence of any explicit pre-deployment calibration, EZ yields a median localization error of 2m and 7m, respectively, in a small building and a large building, which is only somewhat worse than the 0.7m and 4m yielded by the best-performing but calibrationintensive Horus scheme [29] from prior work.
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A survey of indoor positioning systems for wireless personal networks

by Yanying Gu, Anthony Lo, Senior Member, Ignas Niemegeers - IEEE Communications Surveys & Tutorials , 2009
"... Abstract—Recently, indoor positioning systems (IPSs) have been designed to provide location information of persons and devices. The position information enables location-based pro-tocols for user applications. Personal networks (PNs) are de-signed to meet the users ’ needs and interconnect users ’ d ..."
Abstract - Cited by 91 (0 self) - Add to MetaCart
Abstract—Recently, indoor positioning systems (IPSs) have been designed to provide location information of persons and devices. The position information enables location-based pro-tocols for user applications. Personal networks (PNs) are de-signed to meet the users ’ needs and interconnect users ’ devices equipped with different communications technologies in various places to form one network. Location-aware services need to be developed in PNs to offer flexible and adaptive personal services and improve the quality of lives. This paper gives a comprehensive survey of numerous IPSs, which include both commercial products and research-oriented solutions. Evaluation criteria are proposed for assessing these systems, namely security and privacy, cost, performance, robustness, complexity, user pref-erences, commercial availability, and limitations. We compare the existing IPSs and outline the trade-offs among these systems from the viewpoint of a user in a PN.
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Rendered Path: Range-Free Localization in Anisotropic Sensor Networks with Holes

by Mo Li, et al. , 2007
"... Sensor positioning is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). Current localization approaches can be divided into two groups: range-based and range-free. Due to the high costs and critical assumptions, the range-based schemes are often imp ..."
Abstract - Cited by 85 (14 self) - Add to MetaCart
Sensor positioning is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). Current localization approaches can be divided into two groups: range-based and range-free. Due to the high costs and critical assumptions, the range-based schemes are often impractical for WSNs. The existing range-free schemes, on the other hand, suffer from poor accuracy and low scalability. Without the help of a large number of uniformly deployed seed nodes, those schemes fail in anisotropic WSNs with possible holes. To address this issue, we propose the Rendered Path (REP) protocol. To the best of our knowledge, REP is the only range-free protocol for locating sensors with constant number of seeds in anisotropic sensor networks.
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Zee: Zero-effort Crowdsourcing for Indoor Localization

by Anshul Rai, Krishna Kant Chintalapudi, Venkata N. Padmanabhan, Rijurekha Sen - In Proceedings of ACM International Conference on Mobile Computing and Networking (MobiCom
"... Radio Frequency (RF) fingerprinting, based on WiFi or cellular signals, has been a popular approach to indoor localization. However, its adoption in the real world has been stymied by the need for sitespecific calibration, i.e., the creation of a training data set comprising WiFi measurements at kno ..."
Abstract - Cited by 85 (2 self) - Add to MetaCart
Radio Frequency (RF) fingerprinting, based on WiFi or cellular signals, has been a popular approach to indoor localization. However, its adoption in the real world has been stymied by the need for sitespecific calibration, i.e., the creation of a training data set comprising WiFi measurements at known locations in the space of interest. While efforts have been made to reduce this calibration effort using modeling, the need for measurements from known locations still remains a bottleneck. In this paper, we present Zee – a system that makes the calibration zero-effort, by enabling training data to be crowdsourced without any explicit effort on the part of users. Zee leverages the inertial sensors (e.g., accelerometer, compass, gyroscope) present in the mobile devices such as smartphones carried by users, to track them as they traverse an indoor environment, while simultaneously performing WiFi scans. Zee is designed to run in the background on a device without requiring any explicit user participation. The only site-specific input that Zee depends on is a map showing the pathways (e.g., hallways) and barriers (e.g., walls). A significant challenge that Zee surmounts is to track users without any a priori, user-specific knowledge such as the user’s initial location, stride-length, or phone placement. Zee employs a suite of novel techniques to infer location over time: (a) placement-independent step counting and orientation estimation, (b) augmented particle filtering to simultaneously estimate location and user-specific walk characteristics such as the stride length, (c) back propagation to go back and improve the accuracy of localization in the past, and (d) WiFi-based particle initialization to enable faster convergence. We present an evaluation of Zee in a large office building.
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Social Disclosure of Place: From Location Technology to Communication,

by Smith , Consolvo , Lamarca , Hightower , 2005
"... Abstract Communication by location is a very common practice today. To keep pace with this practice, new technology is generating new process of communication. This paper explores a new location-based student interaction service (BuzZme) that I have designed in my Design project. This service will ..."
Abstract - Cited by 76 (9 self) - Add to MetaCart
Abstract Communication by location is a very common practice today. To keep pace with this practice, new technology is generating new process of communication. This paper explores a new location-based student interaction service (BuzZme) that I have designed in my Design project. This service will amplify social interaction by its different features. There are some location-based web services which are providing many features for social interaction. Having some similarity with those web services, my designed service will serve a specific community. Here I have a target to present an easy service for the students of same campus. I have tried to design the functionalities in such way that students can only interact with their campus friends and teachers in secured and flexible process. To support the goal of this paper, I conducted field survey to indentify the possible demand and impact of my service on students. And the analysis of the results will be discussed in detail in this paper.

Locating in Fingerprint Space: Wireless Indoor Localization with Little Human Intervention

by Zheng Yang, Chenshu Wu, Yunhao Liu
"... Indoor localization is of great importance for a range of pervasive applications, attracting many research efforts in the past decades. Most radio-based solutions require a process of site survey, in which radio signatures of an interested area are annotated with their real recorded locations. Site ..."
Abstract - Cited by 62 (10 self) - Add to MetaCart
Indoor localization is of great importance for a range of pervasive applications, attracting many research efforts in the past decades. Most radio-based solutions require a process of site survey, in which radio signatures of an interested area are annotated with their real recorded locations. Site survey involves intensive costs on manpower and time, limiting the applicable buildings of wireless localization worldwide. In this study, we investigate novel sensors integrated in modern mobile phones and leverage user motions to construct the radio map of a floor plan, which is previously obtained only by site survey. On this basis, we design LiFS, an indoor localization system based on off-the-shelf WiFi infrastructure and mobile phones. LiFS is deployed in an office building covering over 1600m 2, and its deployment is easy and rapid since little human interventionis needed. In LiFS, the calibration of fingerprints is crowdsourced and automatic. Experiment results show that LiFS achieves comparable location accuracy to previous approaches even without site survey.
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Cardinality Estimation for Large-scale RFID Systems

by Chen Qian, Hoilun Ngan, Yunhao Liu, Lionel M. Ni - IN PROCEEDINGS OF THE SIXTH ANNUAL IEEE INTERNATIONAL CONFERENCE ON PERVASIVE COMPUTING AND COMMUNICATION (IEEE PERCOM’ 08
"... Counting the number of RFID tags (cardinality) is a fundamental problem for large-scale RFID systems. Not only does it satisfy some real application requirements, it also acts as an important aid for RFID identification. Due to the extremely long processing time, slotted ALOHA-based or tree-based ar ..."
Abstract - Cited by 59 (7 self) - Add to MetaCart
Counting the number of RFID tags (cardinality) is a fundamental problem for large-scale RFID systems. Not only does it satisfy some real application requirements, it also acts as an important aid for RFID identification. Due to the extremely long processing time, slotted ALOHA-based or tree-based arbitration protocols are often impractical for many applications, because tags are usually attached to moving objects and they may have left the reader’s interrogation region before being counted. Recently, estimation schemes have been proposed to count the approximate number of tags. Most of them, however, suffer from two scalability problems: time inefficiency and multiple-reading. Without resolving these problems, large-scale RFID systems cannot easily apply the estimation scheme as well as the corresponding identification. In this paper, we present the Lottery Frame (LoF) estimation scheme, which can achieve high accuracy, low latency, and scalability. LoF estimates the tag numbers by utilizing the collision information. We show the significant advantages, e.g., high accuracy, short processing time and low overhead, of the proposed LoF scheme through analysis and simulations.

Contour Map Matching for Event Detection in Sensor Networks

by Wenwei Xue, Qiong Luo, Lei Chen, Yunhao Liu - In SIGMOD , 2006
"... Many sensor network applications, such as object tracking and disaster monitoring, require effective techniques for event detection. In this paper, we propose a novel event detection mechanism based on matching the contour maps of in-network sensory data distribution. Our key observation is that eve ..."
Abstract - Cited by 54 (9 self) - Add to MetaCart
Many sensor network applications, such as object tracking and disaster monitoring, require effective techniques for event detection. In this paper, we propose a novel event detection mechanism based on matching the contour maps of in-network sensory data distribution. Our key observation is that events in sensor networks can be abstracted into spatio-temporal patterns of sensory data and that pattern matching can be done efficiently through contour map matching. Therefore, we propose simple SQL extensions to allow users to specify common types of events as patterns in contour maps and study energy-efficient techniques of contour map construction and maintenance for our patternbased event detection. Our experiments with synthetic workloads derived from a real-world coal mine surveillance application validate the effectiveness and efficiency of our approach. 1.
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Mining frequent trajectory patterns for activity monitoring using radio frequency tag arrays

by Yunhao Liu, Lei Chen, Jian Pei, Qiuxia Chen, Yiyang Zhao - In Percom , 2007
"... Activity monitoring, a crucial task in many applications, is often conducted expensively using video cameras. Also, effectively monitoring a large field by analyzing images from multiple cameras remains a challenging problem. In this paper, we introduce a novel application of the recently developed ..."
Abstract - Cited by 47 (9 self) - Add to MetaCart
Activity monitoring, a crucial task in many applications, is often conducted expensively using video cameras. Also, effectively monitoring a large field by analyzing images from multiple cameras remains a challenging problem. In this paper, we introduce a novel application of the recently developed RFID technology: using RF tag arrays for activity monitoring, where data mining techniques play a critical role. The RFID technology provides an economically attractive solution due to the low cost of RF tags and readers. Another novelty of this design is that the tracking objects do not need to attach any transmitters or receivers, such as tags or readers. By developing a practical fault-tolerant method, we offset the noise of RF tag data and mine frequent trajectory patterns as models of regular activities. Our empirical study using real RFID systems and data sets verifies the feasibility and the effectiveness of our design. 1.