Communication using ultra wide-band pulse position modulation for in-body sensors

Abstract

One important challenge in medical in-body sensors today is robust transmission to on-body receivers via wireless channels. The miniature in-body sensors are often restricted in physical size and have limited power supply. At the same time, wireless transmission must also cope with large attenuation due to body tissues and organs. Applications such as the capsule endoscope, require high data rates in order to transmit colour video from inside the small intestine. For such applications, ultra wideband (UWB) communication with pulse-position modulation (PPM) is a suitable solution. In this paper we present a complete communication chain for a capsule endoscope with PPM for transmission over multipath channels. Through simulation we evaluate the impact of channel coding and interleaving, channel state estimation and combining, and estimation of the required transmit power, using a realistic channel model.