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Motion Capture Through Walls, Long Distances

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Fine-scale Through-Wall Positioning Using Tunneling RFID Tags
Cheng Qi;Francesco Amato;Billy Kihei;Gregory D. Durgin
2020 IEEE International Conference on RFID (RFID)

It has been shown that Tunneling Tags enable long-range communications and localization in line-of-sight (LoS) with an RFID reader operating in the 5.8 GHz band. This paper demonstrates how a received signal phase-based positioning method can be applied to localize tags in a non-line-of-sight (NLoS) scenario. In particular, a Tunneling Tag provides 20.0 dB more received signal strength than a Semi-passive one when they communicate through a plaster wall. Moreover, when calibration is applied, average distance estimation accuracies of 12.1 cm (percentage error: 2.1%) and 9.2 cm (percentage error: 1.4%) are achieved in LoS and NLoS, respectively. The low-power requirement of the Tunneling Tag and the low EIRP of the reader suggest that these tags can significantly contribute to developing new and low-powered indoor positioning applications.

Foundational Paper on How to Model a Really Complicated Multi-Loop/Coil Inductive System

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Theoretical Modeling of Complicated Inductive Wireless Power Transfer Systems
Scott Roman, Gregory D. Durgin
2020 IEEE International Conference on RFID (RFID)

Inductive RF power transfer designs can be incredibly versatile, designed with a multiplicity of geometries and current paths to focus and enhance the transfer of power. However, most inductive systems in engineering practice are limited to either two-flat-loop systems or several basic coils with simplifying symmetry aspects. Complicated loop designs are largely ignored or untried by engineers because they are notoriously difficult to understand and model. This paper presents a foundational model for inductive systems with an arbitrarily large number of mutually-coupling loops. For the first time, comprehensive first-principle expressions for calculating voltage gain, s-parameters, and transfer efficiencies for these arbitrarily complicated inductive systems are presented and compared to measurements. The final result is a set of tools for designing the next-generation inductive RFID and wireless power transfer systems.

How to Do Motion Capture with RFID Sensor Fusion

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Nonlinear Least-Squares State Estimation for 2D RFID-Based Motion Capture
Qian Yang;David G. Taylor;Gregory D. Durgin
2020 IEEE International Conference on RFID (RFID)

In this paper, we present a general technique for implementing nonlinear least-squares state estimation for a two-dimensional RFID-based motion capture problem that can achieve 1.45 cm localization accuracy without the need for special initialization or tuning processes – a significant improvement over previous results in the literature. We demonstrate various algorithms that use different combinations of received signal strength (RSS), backscatter signal phase, a 3-axis accelerometer, a 3-axis gyrometer, and 3-axis magnetometer measured in a live microwave backscatter system. Permutations involving different nonlinear solvers (Gauss-Newton and Levenberg-Marquardt) and different stack levels (the number of samples in time incorporated into an estimation) are addressed.

A Brief History of the IEEE Council on RFID

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IEEE Council on Radio-Frequency Identification: History, Present, and Future Vision

Fei-Yue Wang;Gisele Bennett;Bassiri-Gharb Nazanin;Yidong Li;Jun Jason Zhang;GregoryDurgin;Shahriar Mirabbasi;Pui Yi Lau;Christopher Valenta;Francesco Amato;T. S. Rangarajan;Mohammad S. Alhassoun

IEEE Journal of Radio Frequency Identification

Year: 2020 | Volume: 4, Issue: 3 | Journal Article | Publisher: IEEE

This article summarizes the history and present state of the IEEE Council on Radio-Frequency Identification (CRFID). The aim, scope, and achievement of CRFID on technical & academic activities, publications, and membership services & education are highlighted, with focus on how CRFID commits and grows resources to achieve its goals for its technical communities. This article also provides the vision and path to the council’s future, and on this path, CRFID is broadening the technological frontiers of IoT, Blockchain, Cyber-Physical Systems (CPS), Cyber-Physical Social Systems (CPSS), Digital Twins, Parallel Systems, Parallel Intelligence, and many other related enabling and transformational techniques.