Acoustical Ranging Techniques in Embedded Wireless Sensor Networked Devices

Location sensing provides endless opportunities for a wide range of applications in GPS-obstructed environments; where, typically, there is a need for higher degree of accuracy. In this article, we focus on robust range estimation, an important prerequisite for fine-grained localization. Motivated by the promise of acoustic in delivering high ranging accuracy, we present the design, implementation and evaluation of acoustic (both ultrasound and audible) ranging systems.We distill the limitations of acoustic ranging; and present efficient signal designs and detection algorithms to overcome the challenges of coverage, range, accuracy/resolution, tolerance to Doppler’s effect, and audible intensity. We evaluate our proposed techniques experimentally on TWEET, a low-power platform purpose-built for acoustic ranging applications. Our experiments demonstrate an operational range of 20 m (outdoor) and an average accuracy 2 cm in the ultrasound domain. Finally, we present the design of an audible-range acoustic tracking service that encompasses the benefits of a near-inaudible acoustic broadband chirp and approximately two times increase in Doppler tolerance to achieve better performance

A Survey of Positioning Systems Using Visible LED Lights

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.As Global Positioning System (GPS) cannot provide satisfying performance in indoor environments, indoor positioning technology, which utilizes indoor wireless signals instead of GPS signals, has grown rapidly in recent years. Meanwhile, visible light communication (VLC) using light devices such as light emitting diodes (LEDs) has been deemed to be a promising candidate in the heterogeneous wireless networks that may collaborate with radio frequencies (RF) wireless networks. In particular, light-fidelity has a great potential for deployment in future indoor environments because of its high throughput and security advantages. This paper provides a comprehensive study of a novel positioning technology based on visible white LED lights, which has attracted much attention from both academia and industry. The essential characteristics and principles of this system are deeply discussed, and relevant positioning algorithms and designs are classified and elaborated. This paper undertakes a thorough investigation into current LED-based indoor positioning systems and compares their performance through many aspects, such as test environment, accuracy, and cost. It presents indoor hybrid positioning systems among VLC and other systems (e.g., inertial sensors and RF systems). We also review and classify outdoor VLC positioning applications for the first time. Finally, this paper surveys major advances as well as open issues, challenges, and future research directions in VLC positioning systems.Peer reviewe

Low‐power global navigation satellite system‐enabled wireless sensor network for acoustic emission localisation in aerospace components

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Acoustic Localization of Bragg Peak Proton Beams for Hadrontherapy Monitoring

[EN] Hadrontherapy makes it possible to deliver high doses of energy to cancerous tumors by using the large energy deposition in the Bragg-peak. However, uncertainties in the patient positioning and/or in the anatomical parameters can cause distortions in the calculation of the dose distribution. In order to maximize the effectiveness of heavy particle treatments, an accurate monitoring system of the deposited dose depending on the energy, beam time, and spot size is necessary. The localized deposition of this energy leads to the generation of a thermoacoustic pulse that can be detected using acoustic technologies. This article presents different experimental and simulation studies of the acoustic localization of thermoacoustic pulses captured with a set of sensors around the sample. In addition, numerical simulations have been done where thermo-acoustic pulses are emitted for the specific case of a proton beam of 100 MeV.This research was funded by the Spanish Agencia Estatal de Investigacion, grant number FPA2015-65150-C3-2-P (MINECO/FEDER).Otero-Vega, JE.; Felis-Enguix, I.; Ardid Ramírez, M.; Herrero Debón, A. (2019). Acoustic Localization of Bragg Peak Proton Beams for Hadrontherapy Monitoring. Sensors. 19(9):1-13. https://doi.org/10.3390/s19091971S113199Kundu, T. (2014). Acoustic source localization. Ultrasonics, 54(1), 25-38. doi:10.1016/j.ultras.2013.06.009Bortfeld, T. (1997). An analytical approximation of the Bragg curve for therapeutic proton beams. Medical Physics, 24(12), 2024-2033. doi:10.1118/1.598116Ahmad, M., Xiang, L., Yousefi, S., & Xing, L. (2015). Theoretical detection threshold of the proton-acoustic range verification technique. Medical Physics, 42(10), 5735-5744. doi:10.1118/1.4929939Knapp, C., & Carter, G. (1976). The generalized correlation method for estimation of time delay. IEEE Transactions on Acoustics, Speech, and Signal Processing, 24(4), 320-327. doi:10.1109/tassp.1976.1162830Adrián-Martínez, S., Bou-Cabo, M., Felis, I., Llorens, C. D., Martínez-Mora, J. A., Saldaña, M., & Ardid, M. (2015). Acoustic Signal Detection Through the Cross-Correlation Method in Experiments with Different Signal to Noise Ratio and Reverberation Conditions. Lecture Notes in Computer Science, 66-79. doi:10.1007/978-3-662-46338-3_7Felis, I., Martínez-Mora, J., & Ardid, M. (2016). Acoustic Sensor Design for Dark Matter Bubble Chamber Detectors. Sensors, 16(6), 860. doi:10.3390/s16060860Bragg, W. H., & Kleeman, R. (1905). XXXIX. On the α particles of radium, and their loss of range in passing through various atoms and molecules. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 10(57), 318-340. doi:10.1080/14786440509463378Janni, J. F. (1982). Energy loss, range, path length, time-of-flight, straggling, multiple scattering, and nuclear interaction probability. Atomic Data and Nuclear Data Tables, 27(2-3), 147-339. doi:10.1016/0092-640x(82)90004-3Jones, K. C., Seghal, C. M., & Avery, S. (2016). How proton pulse characteristics influence protoacoustic determination of proton-beam range: simulation studies. Physics in Medicine and Biology, 61(6), 2213-2242. doi:10.1088/0031-9155/61/6/2213Lai, H. M., & Young, K. (1982). Theory of the pulsed optoacoustic technique. The Journal of the Acoustical Society of America, 72(6), 2000-2007. doi:10.1121/1.388631Sigrist, M. W. (1986). Laser generation of acoustic waves in liquids and gases. Journal of Applied Physics, 60(7), R83-R122. doi:10.1063/1.337089Tam, A. C. (1986). Applications of photoacoustic sensing techniques. Reviews of Modern Physics, 58(2), 381-431. doi:10.1103/revmodphys.58.381Xiang, L., Han, B., Carpenter, C., Pratx, G., Kuang, Y., & Xing, L. (2012). X-ray acoustic computed tomography with pulsed x-ray beam from a medical linear accelerator. Medical Physics, 40(1), 010701. doi:10.1118/1.4771935Assmann, W., Kellnberger, S., Reinhardt, S., Lehrack, S., Edlich, A., Thirolf, P. G., … Parodi, K. (2015). Ionoacoustic characterization of the proton Bragg peak with submillimeter accuracy. Medical Physics, 42(2), 567-574. doi:10.1118/1.4905047De Bonis, G. (2009). Acoustic signals from proton beam interaction in water—Comparing experimental data and Monte Carlo simulation. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 604(1-2), S199-S202. doi:10.1016/j.nima.2009.03.072Kraan, A. C., Battistoni, G., Belcari, N., Camarlinghi, N., Cirrone, G. A. P., Cuttone, G., … Rosso, V. (2014). Proton range monitoring with in-beam PET: Monte Carlo activity predictions and comparison with cyclotron data. Physica Medica, 30(5), 559-569. doi:10.1016/j.ejmp.2014.04.003Patch, S. K., Hoff, D. E. M., Webb, T. B., Sobotka, L. G., & Zhao, T. (2017). Two-stage ionoacoustic range verification leveraging Monte Carlo and acoustic simulations to stably account for tissue inhomogeneity and accelerator-specific time structure - A simulation study. Medical Physics, 45(2), 783-793. doi:10.1002/mp.12681Lehrack, S., Assmann, W., Bertrand, D., Henrotin, S., Herault, J., Heymans, V., … Parodi, K. (2017). Submillimeter ionoacoustic range determination for protons in water at a clinical synchrocyclotron. Physics in Medicine & Biology, 62(17), L20-L30. doi:10.1088/1361-6560/aa81f8Hickling, S., Lei, H., Hobson, M., Léger, P., Wang, X., & El Naqa, I. (2017). Experimental evaluation of x-ray acoustic computed tomography for radiotherapy dosimetry applications. Medical Physics, 44(2), 608-617. doi:10.1002/mp.12039Ardid, M., Felis, I., Martínez-Mora, J. A., & Otero, J. (2017). Optimization of Dimensions of Cylindrical Piezoceramics as Radio-Clean Low Frequency Acoustic Sensors. Journal of Sensors, 2017, 1-8. doi:10.1155/2017/817967

UWB in 3D Indoor Positioning and Base Station Calibration

There are several technologies available for object locating and tracking in outdoor and indoor environments but performance requirements are getting tighter and precise object tracking is still largely an open challenge for researchers. Ultra wideband technology (UWB) has been identified as one of the most promising techniques to enhance a mobile node with accurate ranging and tracking capabilities. For indoor applications almost all positioning technologies require physical installation of fixed infrastructure. This infrastructure is usually expensive to deploy and maintain. The aim of this thesis is to improve the accessibility of the RF-positioning systems by lowering the configuration cost. Real time localisation and tracking systems (RTLS) based on RF technologies pose challenges especially for the deployment of positioning system over large areas or throughout buildings within a number of rooms. If calibration is done manually by providing information about the exact position of the base stations, the initial set-up is particularly time consuming and laborious. In this thesis a method for estimating the position and orientation (x, y, z, yaw, pitch and roll) of a base station of a real time localization system is presented. The algorithm uses two-dimensional Angle of Arrival information (i.e. azimuth and elevation measurements). This allows more inaccurate manual initial survey of the base stations and improves the final accuracy of the positioning. The thesis presents an implementation of the algorithm, simulations and empirical results. In the experiments, hardware and software procured from Ubisense was used. The Ubisense RTLS bases on UWB technology and utilises Angle of Arrival and Time Difference of Arrival techniques. Performance and functionality of the Ubisense RTLS were measured in various radio environments as well as the implementation of the calibration algorithm. Simulations and experiment studies showed that camera calibration method can be successfully adapted to position systems based on UWB technology and that the base stations can be calibrated in a sufficient accuracy. Because of more flexible calibration, the final positioning accuracy of the Ubisense system was as whole in average better.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format