Probabilistic modeling techniques offer a unifying theoretical framework for solving the problems encountered when developing location-aware and location-sensitive applications in wireless radio networks. In this paper we demonstrate the usefulness of the probabilistic modelling framework in solving not only the actual location estimation (positioning) problem, but also many related problems in...

Subscriber radio location techniques are investigated for code-division multiple-access (CDMA) cellular networks. Two methods are considered for radio location: measured times of arrival (ToA) and angles of arrival (AoA). The ToA measurements are obtained from the code tracking loop in the CDMA receiver, and the AoA measurements at a base station (BS) are assumed to be made with an antenna arra...

This research evaluates the quality of GPS signals and their usability for localization in urban environments. GPS signals collected on a Software Defined Radio (SDR) platform in urban canyons in Columbus, Ohio (USA) are processed using a deeply integrated GPS/INS scheme. This architecture allows for coherent signal integration with continuous carrier phase tracking for intervals as long as one...

Zigbee is one of the most exciting wireless sensor network (WSN) technologies for monitoring and control. In our previous research, an integrated Zigbee RFID sensor network was designed as an ‘all-in-one’ system as well as a connectionless inventory tracking solution for Humanitarian Logistics Center (HLC) resource management. Various field trials, which have justified the feasibility and featu...

The population of elderly people is increasing rapidly in many developed nations. Providing safe and comfortable care to aging people is an important social goal. Moreover, obtaining correct activity and location information for an elderly person is an important research goal. This work proposes a novel intelligent RFID-based indoor tracking system for elderly people living alone. The proposed ...

During the last decade with the rapid increase in indoor wireless communications, location-aware services have received a great deal of attention for commercial, public-safety, and a military application, the greatest challenge associated with indoor positioning methods is moving object data and identification. Mobility tracking and localization are multifaceted problems, which have been studie...

We propose a framework for utilizing fixed ultrawideband ranging radio nodes to track a moving target radio node in an environment without guaranteed line of sight or accurate odometry. For the case where the fixed nodes’ locations are known, we derive a Bayesian room-level tracking method that takes advantage of the structural characteristics of the environment to ensure robustness to noise. F...

Rapid advances in wireless technologies and the near ubiquitous nature of portable mobile devices provide an opportunity to develop and deliver new types of location centric applications and services to users. However the majority of the current location based systems lack sufficient granularity and accuracy. This paper attempts to address some of these issues and presents an internal location ...

The Location Stack is a set of design abstractions and sensor fusion techniques for location systems. It employs novel probabilistic techniques such as particle filters to fuse readings from multiple sensor technologies while providing a uniform programming interface to applications. Our implementation is publicly available and supports many location sensor technologies. Specifically, our live ...

Wireless communication technology has been increasingly adopted in various business environments of supply chains. Radio frequency identification technology enables to obtain the real-time information of the dynamics associated with vehicle shipment operations. This paper presents a Markov decision process model for dynamically building the shipment loads using the real-time information of the ...