Integration of UWB and Wireless Pressure Mapping in Surgical Navigation

Wireless technologies are becoming more prevalent in hospital environments. An ultra-wideband (UWB) indoor tracking system is outlined, which has dynamic 3-D real-time root-mean-square error in the range of 5.24-6.37 mm using line-of-sight signals in different experiments. This high 3-D accuracy opens up many new applications to UWB indoor wireless positioning, which includes its use for tracking smart surgical tools and its ability to register relevant objects in the scene such as a spacer block for real-time pressure mapping of the femoral condyles. Experimental results quantifying the operating room (OR) environment for UWB transmission fit to the IEEE 802.15.4a channel model are included. A simulation of our UWB positioning system with interference from an IEEE 802.11a source shows the need for a front-end bandpass filter at our UWB receiver. Both microcantilever and microelectromechanical systems-based wireless pressure sensors are presented including quantitative performance metrics (e.g., hysteresis, sensitivity). The data for these sensors is transmitted over the 315- and 433.92-MHz telemetry bands. These bands are examined for their performance in the OR.