Optimum threshold for ranging based on ToA estimation error analysis

Precision ultra-wideband (UWB) ranging requires accurate estimation of time-of-arrival (ToA). The threshold-based ToA estimation is attractive due to its simplicity. In this paper theoretical closed form expressions of ToA estimation error are derived. A new technique to set the threshold as a function of distance is proposed. ToA estimation error of conventional threshold and distance dependent (DD) threshold setting are analyzed at various signal-to-noise ratios (SNR).