Precise indoor localization systems: Alternative methods for sub-sampling UWB pulses and associated error sources

A millimeter precision indoor ultra-wideband (UWB) localization system has been developed for high accuracy indoor localization applications including surgical navigation. We use two competing sub-sampling techniques in our system: the first technique exploits a small frequency shift of the transmitter clock and the receiver clock; the second technique uses a delay line chip at the receiver side. We discuss the limitations of these sub-sampling systems in the context of achieving sub-mm precision performance for biomedical applications requiring high accuracy indoor localization.