Figure 18 - available via license: Creative Commons Attribution 3.0 Unported
Content may be subject to copyright.
Source publication
A rigorous full-wave solution, via the Finite-Difference-Time-Domain (FDTD) method, is performed in an attempt to obtain realistic communication channel models for on-body wireless transmission in Body-Area-Networks (BANs), which are local data networks using the human body as a propagation medium. The problem of modeling the coupling between body...
Similar publications
Seamless management of producer mobility in named data networks (NDNs) has become an inherent requirement to satisfy the ever-increasing number of mobile user devices and the streaming of widespread real-time multimedia content. In this paper, we first classify the various producer mobility management (MM) schemes into four different approaches. Th...
Data retrieval in Named Data Networking (NDN) is based on content names irrespective of their hosting location. The NDN architecture introduces original naming, forwarding and caching techniques to improve data delivery efficiency. These distinctive techniques make the TCP congestion control scheme not suitable for the NDN architecture. In particul...
The main aim of this study is to measure the technical efficiency and decompose total factor productivity (TFP) growth of Polish crop farms. The novelty of our contribution is threefold. First of all, our work contributes to research on agricultural performance of Central and Eastern European countries in the post-European Union accession period. S...
The wine sector currently lacks nuclear features, which makes Portugal’s producing performance drift away from the frontline world-wide wine producers. The aim of this paper is to evaluate the evolution of the Portuguese wine industry’s performance through the world and national available statistical data. Also, this work tries to evaluate the sust...
Named Data networking(NDN) has emerged as a new communication paradigm designed for efficient dissemination of data. However, mobility issues are not considered sufficiently. Consumer or producer mobility can incur request staleness issue, the loss of Interest and Data packets and communication delay. Through analysis, we consider how to forward th...
Citations
... ε ,, r = 8.51 and tan δ = 0.242. This model has proven to be a good approximation for a layered inhomogeneous phantom with skin, fat, muscle and bone [5][6][7][8]. ...
... 0.047184 f − 0.003434 [1,5] 0.049366 f − 0.005616 [5,10] 0.057179 f − 0.023086 ≥10 ...
... 0.047184 f − 0.003434 [1,5] 0.049366 f − 0.005616 [5,10] 0.057179 f − 0.023086 ≥10 ...
This paper presents a complete and detailed description of the fabrication and measurement of the electromagnetic properties of water-based semi-solid phantoms with emphasis on the analysis of the time evolution of the complex permittivity of several samples stored in different conditions. A known recipe for a 2/3 muscle equivalent phantom is used as test material, and the several phantom sample properties are measured with an in-house developed coaxial probe technique. It is shown that the storing condition is of paramount importance to extend the lifetime of a given phantom. This behavior stems from the way the storing condition affects the water evaporation rate of the sample. In particular, while an unprotected sample can preserve its electromagnetic properties only for a few days, a very well-sealed one can last at least up to a year.
... Extensive study on the effects of different numerical phantoms [18]- [20] in on-body communication scenarios is performed using FDTD. This technique has also been widely used for the investigation of the radiation from implanted devices [21], to evaluate the behavior of body-worn antennas [22], [23]. Frequency-dependent FDTD codes [24]- [26] are developed handling the human body, which is a dispersive and lossy dielectric medium. ...
... The movement of the human body makes this radio channel even more difficult to characterize. Much research has been devoted to characterizing the narrow-band on-body propagation channel [3][4][5][6][7][8][9][10][11][12][13]. In the earlier work, a channel model was derived for body area networks at 400, 900, and 2400 MHz from numerical simulation [3]. ...
This paper presents the experimental investigation of the characterization of the narrowband on-body radio propagation channel at 2.45 GHz. Wearable planar textile monopole antennas (TM) were used in this measurement campaign. The measurements were conducted in the RF-shielded room environment, considering eight on-body radio links. A statistical analysis was conducted on the spectral parameters of the channel to enable the prediction and modeling of dynamic on-body radio propagation characteristics. The empirical data were fitted to several well-known statistical models to determine the model that provided the best fit for the data. The results showed that the path loss exponent was consistent with the results of previous studies. The results also demonstrated that lognormal distribution was found to be the best fit for path loss in dynamic on-body radio propagation channel.
... An analysis of WBANs and sensor network operating in the proximity of a human body is often carried out with the use of full-wave electromagnetic simulation software which also implements a numerical model of the human body. The Finite Difference Time Domain (FDTD) method is widely used for this type of studies [10]. In our research we use the XFdtd ® FDTD implementation from REMCOM, Inc. (State College, PA, USA) [11]. ...
We investigate a case of automated energy-budget-aware optimization of the physical position of nodes (sensors) in a Wireless Body Area Network (WBAN). This problem has not been presented in the literature yet, as opposed to antenna and routing optimization, which are relatively well-addressed. In our research, which was inspired by a safety-critical application for firefighters, the sensor network consists of three nodes located on the human body. The nodes communicate over a radio link operating in the 2.4 GHz or 5.8 GHz ISM frequency band. Two sensors have a fixed location: one on the head (earlobe pulse oximetry) and one on the arm (with accelerometers, temperature and humidity sensors, and a GPS receiver), while the position of the third sensor can be adjusted within a predefined region on the wearer’s chest. The path loss between each node pair strongly depends on the location of the nodes and is difficult to predict without performing a full-wave electromagnetic simulation. Our optimization scheme employs evolutionary computing. The novelty of our approach lies not only in the formulation of the problem but also in linking a fully automated optimization procedure with an electromagnetic simulator and a simplified human body model. This combination turns out to be a computationally effective solution, which, depending on the initial placement, has a potential to improve performance of our example sensor network setup by up to about 20 dB with respect to the path loss between selected nodes.
... An in-depth simulation-based analysis of the coupling between body mounted antennas using computational electrodynamics methods, such as the FDTD method and numerical phantoms, can be found in literature (e.g. Bringuier and Mittra, 2012;Yan Zhao et al., 2009;Chen and Babij, 1996;Reusens et al., 2008). These considerations focus on the case of WBAN operating in free space where the influence of reflecting objects in the environment around the human body is neglected (Chen and Babij, 1996;Reusens et al., 2008). ...
Purpose
The paper aims to compare properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss modelling in narrowband and ultra-wideband on-body Wireless Body Area Networks. One of the models has been proposed by the authors.
Design/methodology/approach
Two simplified numerical and two physical phantoms for Body Area Network on-body channel computer simulation and field measurement results are presented and compared.
Findings
Computer simulations and measurements which were carried out for the proposed simplified 6-cylinder model with various antenna locations lead to the general conclusion that the proposed phantom can be successfully used for experimental investigation and testing of on-body WBANs both in ISM and UWB IEEE 802.15.6 frequency bands.
Research limitations/implications
Usage of the proposed phantoms for the simulation/measurement of the Specific Absorption Rate and for off-body channels are not within the scope of this paper.
Practical implications
The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. The model is most suitable for wearable antenna radiation pattern simulation and measurement.
Originality/value
A new 6-cylinder phantom has been proposed. The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies.
... Such characterization can employ analysis for simple conditions or sophisticated computer simulation models for more complex settings, yet in the end, the most reliable characterization—and validation of any analytical or computer models—must employ measurements . For the AG channel, existing measurements are Note that a thorough channel characterization precedes development of all modern communication system designs, e.g., for terrestrial cellular [5], [6], wireless personal area networks [7], and short-range terahertz communication systems [8]. As data rates and numbers of system users have increased over the years, channel characterizations have become essential parts of the system design process. ...
... In that case choosing radio propagation channel models for BAN is difficult because expected values of path loss through the body are high (up to about 90 dB) and may be critical for the proper operation of the network [2,3]. An in-depth simulation based analysis of the coupling between body mounted antennas using computational electrodynamics methods, such as the finite difference time domain (FDTD) method and numerical phantoms, can be found in literature, e.g., [4][5][6][7]. However, some of these considerations focus on an unrealistic case of BAN operating in free space and the influence of reflecting objects in the environment around the human body is neglected [6,7]. ...
In this paper the influence of an example indoor environment on narrowband radio channel path loss for body area networks operating around 2.4 GHz is investigated using computer simulations and on-site measurements. In contrast to other similar studies, the simulation model included both a numerical human body phantom and its environment-room walls, floor and ceiling. As an example, radio signal attenuation between two different configurations of transceivers with dipole antennas placed in a direct vicinity of a human body (on-body scenario) is analyzed by computer simulations for several types of reflecting environments. In the analyzed case the propagation environments comprised a human body and office room walls. As a reference environment for comparison, free space with only a conducting ground plane, modelling a steel mesh reinforced concrete floor, was chosen. The transmitting and receiving antennas were placed in two on-body configurations chest-back and chest-arm. Path loss vs. frequency simulation results obtained using Finite Difference Time Domain (FDTD) method and a multi-tissue anthropomorphic phantom were compared to results of measurements taken with a vector network analyzer with a human subject located in an average-size empty cuboidal office room. A comparison of path loss values in different environments variants gives some qualitative and quantitative insight into the adequacy of simplified indoor environment model for the indoor body area network channel representation.
This paper explores high data rate microwave communication through fat tissue in order to address the wide bandwidth requirements of intrabody area networks. We have designed and carried out experiments on an IEEE 802.15.4-based WBAN prototype by measuring the performance of the fat tissue channel in terms of data packet reception with respect to tissue length and power transmission. This paper proposes and demonstrates a high data rate communication channel through fat tissue using phantom and
ex-vivo
environments. Here, we achieve a data packet reception of approximately 96% in both environments. The results also show that the received signal strength drops by ∼1 dBm per 10 mm in phantom and ∼2 dBm per 10 mm in
ex-vivo
. The phantom and
ex-vivo
experimentations validated our approach for high data rate communication through fat tissue for intrabody network applications. The proposed method opens up new opportunities for further research in fat channel communication. This study will contribute to the successful development of high bandwidth wireless intrabody networks that support high data rate implanted, ingested, injected, or worn devices.
