Recently, we proposed a wireless ambulatory gait analysis system that provides a high ranging accuracy using ultra-wideband (UWB) transceivers. In this paper, we further investigate the performance of our proposed system including ranging using suboptimal templates, power consumption, and sensor-fusion. We show that the proposed system is capable of providing a 1.1 mm ranging accuracy (1.17 cm for current systems) at a signal-to-noise-ratio (SNR) of 20 dB using suboptimal-based receivers in industry accepted body-area-network UWB channels. For the angular-displacement, our system provides an accuracy that is less than 1o for the knee-flexion angle. This accuracy is superior to the accuracy reported in the literature for current technologies (less than 4o). Finally, we propose the integration of UWB sensors with force sensors. The system performance and design parameters are investigated using simulations and actual measurements. Ultimately, the proposed system is suitable for taking accurate measurements, and for tele-rehabilitation.
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