Open AccessDifferential FMCW‐LiDAR for breaking the limit of laser coherence
Author(s) -
Tsuchida H.
Publication year - 2020
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2020.0186
Subject(s) - lidar , ranging , coherence (philosophical gambling strategy) , optics , laser , continuous wave , subcarrier , coherence length , retroreflector , differential (mechanical device) , physics , computer science , telecommunications , orthogonal frequency division multiplexing , channel (broadcasting) , superconductivity , quantum mechanics , thermodynamics
One of the serious limitations in frequency‐modulated continuous wave light detection and ranging (FMCW‐LiDAR) is the maximum ranging distance as imposed by the coherence of light sources. The author proposes and demonstrates a new technique for overcoming the limitation using differential detection scheme between the frequency‐fixed carrier and frequency‐modulated subcarrier, which are generated from a single laser source. In the proof‐of‐principle experiment, two reflection points with a 3 m separation are clearly resolved at distances 192.2 m and 1.504 km using a distributed feedback (DFB) laser with the coherence length of 70 m.