Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Experimental Characterization of a UWB Channel for Body Area Networks | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2011 Article ID 703239 11 pages doi 2011 703239 Research Article Experimental Characterization of a UWB Channel for Body Area Networks Lingli Xia Stephen Redfield and Patrick Chiang VLSI Research Group Oregon State University Corvallis OR 97331 USA Correspondence should be addressed to Lingli Xia xia@ Received 28 October 2010 Accepted 14 January 2011 Academic Editor Philippe De Doncker Copyright 2011 Lingli Xia et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Ultrawideband UWB communication is a promising technology for wireless body area networks BANs especially for applications that require transmission of both low and high data rates with excellent energy efficiency. Therefore understanding the unique UWB channel propagation characteristics around the human body is critical for a successful wireless system especially for insuring the reliability of important vital sign data. Previous work has focused only on on-body channels where both TX and RX antennas are located on the human body. In this paper a 3-5 GHz UWB channel is measured and analyzed for human body wireless communications. Beyond the conventional on-body channel model line-of-sight LOS and non-line-of-sight NLOS channel models are obtained using a TX antenna placed at various locations of the human body while the RX antenna is placed away from the human body. Measurement results indicate that the human body does not significantly degrade the impedance of a monopole omnidirectional antenna. The measured path loss and multipath analysis suggest that a LOS UWB channel is excellent for low-power high-data-rate transmission while NLOS and on-body channels need to be reconfigured to operate at a lower data rate due to .
