Performance and limitations of dual-comb based ranging systems

TL;DR

This paper evaluates the performance and limitations of dual-comb LiDAR systems, focusing on the trade-offs between precision, non-ambiguity range, and the effects of comb parameters on measurement capabilities.

Contribution

It introduces a performance factor to quantify trade-offs, analyzes the influence of comb envelope and repetition rate, and explores conditions leading to measurement impossibility.

Findings

Precision is limited by the comb's repetition rate.

The non-ambiguity range depends on the comb's repetition rate.

Non-linear interference effects can prevent target resolution.

Abstract

Dual-comb LiDARs have the potential to perform high-resolution ranging at high speed. Here, through an implementation involving electro-optic modulators and heterodyne detection, we quantify the ranging systems trade-off between precision and non-ambiguity range (NAR) using a unique performance factor. We highlight the influence of the comb amplitude envelope on the precision with a distance measurement limited by the repetition rate of the optical comb. The influence of the combs repetition rate on the NAR and on the precision is illustrated through a setup allowing distance measurement with a tunable NAR. Finally, we demonstrate the impossibility to resolve different targets, quantify the impact on the measured distance and develop on the conditions in which non-linear effects of the interference make the measurement impossible.