Showing papers by "Jianqing Wang published in 2011"
TL;DR: In this article, a dual-mode impulse radio ultra-wideband (IR-UWB) system, which combines body channel communication for wearable on-body transmission with conventional UWB communication for in-body to onbody transmission, is proposed.
Abstract: A dual-mode impulse radio ultra-wideband (IR-UWB) system, which combines body channel communication for wearable on-body transmission with conventional UWB communication for in-body to on-body transmission, is proposed. The basic system structure is presented, and the path loss characteristics are derived based on numerical analysis and measurement. Moreover, through a bit error rate performance analysis, the required transmit power against communication distance shows the feasibility for on-body and in-body transmissions at a data rate of at least 10 Mbps.
12 citations
6 citations
26 Oct 2011
TL;DR: An EGC diversity system for implant BANs is presented which can improve the communication performance and the bit error rate (BER) performance by theoretical analysis and two approximation methods are introduced.
Abstract: This paper evaluates the performance of an equal gain combining (EGC) diversity receiver for implant body area networks (BANs) at 400 MHz medical implant communication service (MICS) band. To begin with, in order to analyze the performance of the EGC diversity receiver, we perform finite-difference time-domain (FDTD) simulations on implant BAN propagation with a numerical human model, and investigate the propagation characteristics of implant BAN signals. Then, this paper presents an EGC diversity system for implant BANs which can improve the communication performance and evaluates the bit error rate (BER) performance by theoretical analysis. In the theoretical analysis, it is difficult to analytically derive the probability density function (pdf) on the combined signal-to-noise power ratio (SNR) at the EGC receiver output. Therefore, we introduce two approximation methods such as the moment generating function (MGF) method and the curve fitting method. The paper demonstrates that the performances by the theoretical analyses with the two approximation methods are almost corresponding to those by the computer simulations.
6 citations
TL;DR: The bit error rate performance has shown the validity of the ultra wideband impulse radio system in the in-body to off-body chest channel and good agreement with the FDTD-calculated result in terms of key communication metrics.
Abstract: The objective of this study is to investigate the feasibility of an ultra wideband (UWB) impulse radio system for in-body to off-body wireless communication for biomedical applications. At first, a UWB antenna is designed in the UWB low band for implant use in the chest. Then the channel model is extracted and established based on the finite difference time domain (FDTD) simulation with an anatomical human body model. The established channel model consists of a small set of parameters for generating discrete time impulse responses. The generated model shows good agreement with the FDTD-calculated result in terms of key communication metrics. For effective communication over the multipath-affected channel, the pulse position modulation is employed and a 2-finger RAKE structure with a constant temporal delay is proposed in the receiver. The bit error rate performance has shown the validity of the system in the in-body to off-body chest channel.
4 citations
TL;DR: In this article, the authors measured the dielectric properties of 2.5 ml whole blood at 25 °C for 10 normal healthy subjects and 9 hemodialysis patients and found that the measured results on healthy subjects show good agreement with the data reported by Gabriel for human blood at 37 °C, while they provide different dispersion characteristics of straight lines for their Cole-Cole plots.
Abstract: Before evaluating the quality of hemodialysis from the limited volume of human blood using a commercially available open-ended coaxial probe, we previously measured the complex relative permittivity of pure water from 200 MHz to 6 GHz with respect to its measured liquid volume, and found that 1.9 ml of water in a beaker with a diameter of 24 mm and a depth of 2 mm gives a variation within ± 0.5% for the real part and ± 7% for the imaginary part. Based on the above finding, we measured the dielectric properties of 2.5 ml whole blood at 25 °C for 10 normal healthy subjects and 9 hemodialysis patients. The measured results on healthy subjects show good agreement with the data reported by Gabriel for human blood at 37 °C, while they provide different dispersion characteristics of straight lines for their Cole–Cole plots. The measured results on the patients give further different dispersion characteristics versus the healthy subjects. In an investigation of the above differences statistically, Student's t-test revealed that the permittivity at infinite frequency for the Cole–Cole plots is significantly different with a level of 1% among its averaged values for normal healthy subjects and patients before dialysis. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(12): 56–61, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11421
2 citations
20 Oct 2011
TL;DR: This study divides the rat cage in the exposure box into nine small areas, and derives the stay frequency of rat in each area based on the classification of the documentary photos of rat activity, and calculates the statistical characteristics of the whole-body average SAR for the rats during the entire exposure period.
Abstract: For a whole-body exposure setup of rats, the rats can freely move in the cage in most cases. In order to determine the specific absorption rate (SAR) variation during the entire exposure period, a statistical analysis for the rat activity behavior in the exposure period is necessary. In this study, we divide the rat cage in the exposure box into nine small areas, and derive the stay frequency of rat in each area based on the classification of the documentary photos of rat activity. Using the stay frequency as a weighting factor, we calculate the statistical characteristics of the whole-body average SAR for the rats during the entire exposure period. Such an approach gives a high quality determination of the exposure level.
2 citations
01 Jan 2011
TL;DR: In this article, the effect of environment reflection on the average bit error rate performance was investigated for a typical impulse radio UWB system, and it was demonstrated that a complete body area channel model can be regarded as a combination of the on-body propagation characteristic and additional components from the environment.
Abstract: SUMMARY This study aims how to contain the environment reflection in a dynamic on-body ultra wideband (UWB) channel model. Based on a measurement approach, it is demonstrated that a complete body area channel model can be regarded as a combination of the on-body propagation characteristic and additional components from the environment. Based on such a channel model, the effect of environment reflection on the average bit error rate performance was investigated for a typical impulse radio UWB system.
2 citations
TL;DR: It is demonstrated that a complete body area channel model can be regarded as a combination of the on-body propagation characteristic and additional components from the environment, and the effect of environment reflection on the average bit error rate performance was investigated for a typical impulse radio UWB system.
Abstract: This study aims how to contain the environment reflection in a dynamic on-body ultra wideband (UWB) channel model. Based on a measurement approach, it is demonstrated that a complete body area channel model can be regarded as a combination of the on-body propagation characteristic and additional components from the environment. Based on such a channel model, the effect of environment reflection on the average bit error rate performance was investigated for a typical impulse radio UWB system.
2 citations
26 Oct 2011
TL;DR: A quantitative performance analysis of diversity effect for in-body to on-body ultra wideband (UWB) transmission for capsule endoscope finds that a diversity scheme is expected to provide an effective improvement on this wireless link performance.
Abstract: The objective of this study is to perform a quantitative performance analysis of diversity effect for in-body to on-body ultra wideband (UWB) transmission for capsule endoscope UWB technology has a potential to provide real-time image transmission from inside to outside of human body owing to its inherent features However, it suffers from large attenuation together with shadowing in human tissues In view of this distinctive property, a diversity scheme is expected to provide an effective improvement on this wireless link performance Based on finite-difference time-domain (FDTD) numerically-derived in-body to on-body characteristics, we derive probability density function (PDF) for combined communication channels with two different approximation methods and compare their accuracy at first Then we calculate average bit error rate (BER) with pulse position modulation (PPM) and on-off keying (OOK) modulation scheme to clarify the possible diversity effect
1 citations