Indoor Channel Measurements and Models at 2.4 GHz in a Hospital

Abstract

In order to facilitate the deployment of wireless systems in medical environments, indoor channel measurements at 2.4 GHz have been performed in a hospital. In these environments, monitoring applications are of particular interest, where a patient carrying a medical body area network (MBAN) transmits data to a fixed receiver. The receiving node may be placed in practice at different locations, for instance inside a patient room (in a monitoring station) or as a base station in the corridor. In such scenarios, transmitter mobility around the hospital floor results in different channels that may have very different properties, which in turn influences the performance of the wireless link. Based on measurements in several line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios, across different hospital areas, we determine the large-scale path loss and several small-scale fading parameters. Applying the proposed channel models in a simulation environment for IEEE 802.15.4 systems, we find that the simulated performance matches well the measured performance using IEEE 802.15.4 devices. The performance results illustrate the topologies and cases for which acceptable performance can be achieved in the presence of IEEE 802.11g interference.