Body-centric communications is an important part of fourth-generation personal communications systems. Like the mobile cellular communication channel, on-body communication channels are affected by fading. In this paper, the effect of diversity for on-body communication channels is investigated. Measurements were taken in both an anechoic and typical indoor environments, with random body movements. Three different types of antennas were used. The diversity gain was calculated by plotting the cumulative distribution functions (CDF) for five body channels. Significant diversity gain values are observed for the nonline-of-sight channels and dynamic channels involving large body movements. The uplink and downlink diversity performance was found to be similar
The effect of textiles on propagation along the body at 60 GHz is studied. A Green's function representation is used to investigate analytically the field excited by an infinitesimal dipole over a multilayer structure representing a flat skin model and clothing. The propagation between two rectangular open-ended waveguides is studied numerically and analytically in terms of path gain. Furthermore, the effect of an air gap between the textile and phantom is considered. Results show that the presence of a textile over a skin-equivalent phantom, as well as an air gap between them, induces a typical decrease of the path gain by 2-5 dB, but it doesn't significantly affect the path gain exponent. In all considered scenarios the power decay exponent is around 3.6.
Abstract-A feasibility study where small wireless transceivers are used to classify some typical limb movements used in physical therapy processes is presented. Wearable wireless low-cost commercial transceivers operating at 2.4 GHz are supposed to be widely deployed in indoor settings and on people's bodies in tomorrow's pervasive computing environments. The key idea of this work is to exploit their presence by collecting the received signal strength measured between those worn by a person. The measurements are used to classify a set of kinesiotherapy activities. The collected data are classified using both Support Vector Machine and K-Nearest Neighbour methods, in order to recognise the different activities. Index Terms- I. INTRODUCTIONHE increasing improvements of wireless technology and miniaturized sensors made possible the proliferation of wireless sensor networks. These communications networks are one of the first real world examples of pervasive computing: they are composed of small, smart and cheap sensing devices that promise to eventually permeate the environment. We may face a not so distant future where small sensors, all capable of wireless communication, are ubiquitously deployed in the environment and on people's body. TExtensive attention has been focused in the literature on wireless sensor networks, especially in the framework of wireless body sensor networks [1]. In particular, wearable wireless systems were developed to detect, track and understand people's behaviour. In recent years, the detection of body posture and activity received a significant interest for their application in sports, medicine and military. Recognizing people's activities is also a key issue in Assisted Living (AL) applications, where it can be useful for example to rate how a person performs routine activities [2,3].One further field of application is kinesiotherapy, where the aim is to provide monitoring of physical therapies for patients who have suffered a stroke, multiple sclerosis, joint replacements or reconstructions, amputation, brain and spinal cord injury, or some motor function disability resulting from Parkinson's disease [4][5][6]. For these cases, wireless body Manuscript received….Anda R. Guraliuc and Paolo Nepa are with the Department of Information Engineering, University of Pisa, Italy (via Caruso 16, I-56122, Pisa, Italy, phone: +39 050 2217511; fax: +39 050 2217522; e-mail: {anda.guraliuc, paolo.nepa}@iet.unipi.it).Paolo Barsocchi and Francesco Potortì are with the ISTI Institute of CNR (via Moruzzi 1, I-56124, Pisa, Italy, e-mail: {paolo.barsocchi, potorti}@isti.cnr.it): their work is supported in part by the European Commission in the framework of the FP7 project UNIVERSAAL (contract N. 247950).sensor networks could replace the existing wired telemetry systems [7], allowing remotely supervised kinesiotherapy. In a typical wearable Wireless Body Area Network (WBAN) scenario, a patient wears some sensors that form an on-body sensor network, while an off-body base station registers data collected...
The design of a rectangular dielectric resonator antenna (DRA) operating in the Ku frequency band is addressed in this letter. Since the DRA has to be used as the radiating element of a transmitting array of active integrated antennas, its input impedance must exhibit a proper resistive load at the fundamental resonance frequency, as well as a dominant reactive behavior, either inductive or capacitive, at higher harmonics. Then, the configuration here proposed is a slot-coupled DRA where harmonic tuning is performed by resorting to the introduction of a couple of additional slots parallel to the conventional main coupling slot. The modified DRA is characterized by the same complexity level as the nontunable counterpart. Samples of simulation results are shown to demonstrate the capabilities of the proposed slot-based harmonic tuning technique for rectangular DRAs
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.