Title: Off-body UWB channel characterisation within a hospital ward environment

Authors: Philip A. Catherwood, William G. Scanlon

Addresses: The Nanotechnology and Integrated BioEngineering Centre, University of Ulster, Shore Road, Newtownabbey, BT37 0QB, UK. ' Institute of Electronics, Communications and Information Technology, The Queen's University of Belfast, Queen's Road, Belfast, BT3 9DT, UK

Abstract: Received signal strength measurements and delay statistics are presented for both a stationary and mobile user equipped with a wearable UWB radio transmitter (TX) within a hospital environment. The measurements were made for both waist and chest mounted antennas using RF-over-fibre technology to eliminate any spurious electromagnetic scattering effects associated with metallic coaxial cables. The results show that received signal strength values were dependent on whether transmit and receive antennas had line of sight (LOS) and were also affected by body-shadowing and antenna-body position. For mobile conditions, received signal strength tended to be log normally distributed with non-LOS (NLOS) links having significantly lower mean values. Excess time delay results for mobile user tests were best described by the Weibull distribution. Overall, the results favoured the chest mounted antenna position, with higher mean signal levels, reduced mean excess delay and less difference between LOS and NLOS channels.

Keywords: ultra-wideband communications; UWB; body-centric communications; off-body communications; wearable computing; statistical channel characterisation; channel sounding; e-health; electronic healthcare; medical applications; hospital wards; chest mounted antennas; waist mounted antennas; RF-over-fibre.

DOI: 10.1504/IJUWBCS.2010.034307

International Journal of Ultra Wideband Communications and Systems, 2010 Vol.1 No.4, pp.263 - 272

Published online: 31 Jul 2010 *

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