Material distributive topology Optimization of uwb antennas for Wban applications

Abstract

The advent of miniaturization of sensors and actuators and continuous improvement in the wireless communication technology makes Wireless Body Area Network (WBAN) as an emerging technology to improve the quality of life. WBAN incorporates many small, energy efficient, ow cost, robust wearable and/or implanted sensors for collecting and sharing the information around the human body in order to observe the functionalities of vital organs. A WBAN offers many promising, new applications in medicine, defence, emergency services, sport and multimedia gaming. WBAN applications can be divided into different scenarios such as off-body, on-body and in-body communications, depending on the communication needs and requirements. Each of these scenarios uses a different radio channel and has a different set of requirements for the antenna. Antennas are the essential component for wearable devices in WBAN and they play a vital role in optimizing the radio system performance. When the antenna is placed in or close to a human body (lossy medium), the performances change from that of free space operation. For WBAN antennas, he presence of the human body in the proximity of the radiating structure reduces the radiation efficiency and gain. This is due to electromagnetic absorption in body tissues, which results in frequency detuning, radiation pattern distortion and variation of antenna impedance. The architecture of IEEE 802.15.6 suggests that to meet the requirements of wireless body area networks, Impulse Radio Ultra-WideBand (IR-UWB) technology is the suitable candidate. IR-UWB system is capable of achieving high data rate with low power consumption for short range communications and it offers very good immunity to multipath interference newline