Time-Frequency Range Estimation Method for Pulsed LiDAR
Daniel Bastos, Alexandre S. Brandão, Abel Lorences-Riesgo, Paulo P. Monteiro, Arnaldo S. R. Oliveira, D. A. Pereira, Hadi Z. Olyaei, Miguel V. Drummond
Abstract
Light detection and ranging (LiDAR) is the key sensor behind the 3D perception of self-driving vehicles. The range, precision and accuracy of a LiDAR sensor mainly depend on how each received pulse is captured, sampled and processed. However, to the best of our knowledge, such a topic is yet to be investigated in depth. This work aims to fill such a gap by introducing a new range estimation method. The method takes only 3 samples from the rising edge of the received pulse and combines two simple estimation techniques: time-domain edge detection and frequency-domain phase estimation. The proposed method was demonstrated over a dynamic range of 45 dB, proving to be robust over the entire interval. Sub-centimeter precision and accuracy were achieved over a dynamic range of 24 dB. The obtained estimations are bounded by a derived theoretical limit that is identical to a Cramér-Rao lower bound of a phase estimator.