UWB Channel Characterization for Wireless Capsule Endoscopy Localization

Wireless capsule endoscopy (WCE) is a medical device for the inspection of some parts of the gastrointestinal (GI) tract. Currently, WCE transmits to the outside low resolution video, although high quality images would be necessary for improving the detection of diseases. Ultra wideband (UWB) frequency band is a good candidate to achieve such requirement due to its large available bandwidth. Besides, the knowledge of the exact location of WCE would also help physicians to locate the suspicious tissue so diagnosis time could be shortened. Received Signal Strength (RSS) based localization is one of the simplest localization techniques. However, RSS localization requires a good knowledge of the path loss model, what is not easy for in-body communications. The objective of this paper is to provide a review of the problem of modelling the path loss for WCE in UWB as well as give implementation guidelines for WCE localization.