Accurate TOA Estimating UWB-IR Transceiver for Ranging System in Multi-Path Environment

In this work, an ultra-wideband impulse radio (UWB-IR) transceiver with accurate time-of-arrival (TOA) estimation for a ranging/positioning system was developed for wireless sensor network applications. The system uses an impulse radio characterized by a low duty cycle and direct-sequence spreading, which enable very precise ranging and good receiver sensitivity. An algorithm enabling the TOA of the first-path signal to be measured accurately in a multi-path environment with simple, low-power and low cost implementations was proposed. UWB chips with CMOS 0.18-µm technology and UWB transceiver modules performed that the accuracy of the proposed ranging system is 18.5cm in a closed space.