Wearable and Implantable Wireless Body Area Networks

Abstract

Using wireless technology for remote patient monitoring has already taken place in hospitals around the world to support diagnostic and therapeutic functions. Although, a large number of wireless medical systems have been reported in the literature, they have been designed for specific applications that cover limited number of sensors and patients. Future wireless medical monitoring systems should be used in a wireless body area network (WBAN) scheme in order to operate in a larger area in hospital environments. They should be able to incorporate with other wireless systems such as Bluetooth, WiFi and short-range wireless sensor systems such as ZigBee. Installing an interference free wireless medical network for monitoring physiological parameters in a medical center may be quite challenging since there are a number of other wireless systems or equipments (e.g. Wi-Fi, Bluetooth, ZigBee, Microwave oven) operating already for different purposes. Thus it is very crucial to design an interference free wireless system for a WBAN in medical applications. In addition to unlicensed ISM bands, there are medical bands such as MICS (Medical Implant Communication Service) and WMTS (Wireless Medical Telemetry Service) that are specifically regulated for medical monitoring by communication commissions around the world. The recent short-range low data rate ultra-wideband (UWB) technology is another attractive technology that started to appear for body area network applications due to its low transmitter power. Low power operation is essential for sensor nodes in a wireless body area network application as it determines the life time and the size of the device. It is therefore desirable to use a wireless standard (or a wireless chip) that will provide low power consumption and has a minimum transmitted power that still meets the required range of the body area networks. Recent developments have focused on the designs of individual wireless sensor electronics that can be used as an implantable and wearable node to detect signals such as EEG, ECG, pulse rate and temperature. This work will review the recent advances and relevant patents in wireless body area network applications. Issues related to hardware implementations, software and wireless protocol designs for a complete wireless body area network application have been addressed.