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Prior Models for Indoor Super-Resolution Time of Arrival Estimation

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We propose a scheme for super-resolution estimation of the time of arrival of a radio signal which makes use of a prior model of the radio propagation conditions. The method is based on examination of the leading edge of the channel impulse response, and comparison with a database of leading edge shapes generated by Monte Carlo simulation. We also propose an efficient implementation, which makes the method practical for mobile devices with limited computational power. We verify the performance of the method using actual measured data, taken in a number of different situations, and show improved performance over other super-resolution methods proposed in the literature.
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... Equation (34) creates the Rayleigh fading. The variance σ 2 k is the average power of the k path, so the strength of the paths within the clusters is given as [45,46]: ...
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... There have been many approaches reported in the literature that attempt to improve TOA estimation of bandlimited signals in the presence of noise; these approaches can be summarised at "super-resolution" algorithms. For example, (Humphrey & Hedley, 2008;Humphrey & Hedley, 2009) provide a comparison of several techniques, including the well known MUSIC super-resolution algorithm and an algorithm based on a database of pulse templates in multipath situations, which is shown to be superior to MUSIC. However, these methods are computationally intensive, so a simpler, low computational direct approach based on the characteristics of the leading edge of multipath pulses is suggested in the following subsections. ...
Chapter
For a radiolocation system the position of an object is determined using some characteristic of the radio frequency signal. These characteristics could include the signal strength, the signal phase (for angle of arrival measurements) or the propagation time-of-flight (TOF) from the transmitter to the receive.
... In narrowband channels, where no beamforming antennas are available, super-resolution methods are often used. These methods [50,51,55,63,70] utilize super-resolution methods as ...
Thesis
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Half TitleTitleCopyrightDedicationContentsPreface
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Towards location aware mobile ad hoc sensors A Systems Engineering Approach to Wireless Information Networks The Second Edition of this internationally respected textbook brings readers fully up to date with the myriad of developments in wireless communications. When first published in 1995, wireless communications was synonymous with cellular telephones. Now wireless information networks are the most important technology in all branches of telecommunications. Readers can learn about the latest applications in such areas as ad hoc sensor networks, home networking, and wireless positioning. Wireless Information Networks takes a systems engineering approach: technical topics are presented in the context of how they fit into the ongoing development of new systems and services, as well as the recent developments in national and international spectrum allocations and standards. The authors have organized the myriad of current and emerging wireless technologies into logical categories: * Introduction to Wireless Networks presents an up-to-the-moment discussion of the evolution of the cellular industry from analog cellular technology to 2G, 3G, and 4G, as well as the emergence of WLAN and WPAN as broadband ad hoc networks * Characteristics of Radio Propagation includes new coverage of channel modeling for space-time, MIMO, and UWB communications and wireless geolocation networks * Modem Design offers new descriptions of space-time coding, MIMO antenna systems, UWB communications, and multi-user detection and interference cancellation techniques used in CDMA networks * Network Access and System Aspects incorporates new chapters on UWB systems and RF geolocations, with a thorough revision of wireless access techniques and wireless systems and standards Exercises that focus on real-world problems are provided at the end of each chapter. The mix of assignments, which includes computer projects and questionnaires in addition to traditional problem sets, helps readers focus on key issues and develop the skills they need to solve actual engineering problems. Extensive references are provided for those readers who would like to explore particular topics in greater depth. With its emphasis on knowledge-building to solve problems, this is an excellent graduate-level textbook. Like the previous edition, this latest edition will also be a standard reference for the telecommunications industry.
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