Towards sub-millimeter accuracy in UWB positioning for indoor medical environments

Ultra wideband (UWB) positioning systems are increasingly used in indoor environments since commercial systems can provide 3-D accuracy of a few centimeters. Many applications exist in medicine for UWB positioning which includes tracking personnel, assets, and surgical navigation. We have designed a UWB positioning system with millimeter accuracy. Certain applications, including surgical navigation, have even more stringent accuracy requirements in the sub-millimeter range. Many challenges must be overcome to achieve sub-millimeter accuracy including indoor multipath interference, system clock jitter and drift, local oscillator phase noise, sampling-rate limitations, and phase center error. This paper discusses sub-millimeter accuracy in UWB positioning for medical applications and outlines key challenges faced in achieving it with our UWB positioning system. Solutions to these challenges are also outlined followed by a discussion of future work needed to integrate the entire system.