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A comb-calibrated FMCW LADAR for absolute distance measurements

Published

Author(s)

Esther Baumann, Fabrizio R. Giorgetta, Ian R. Coddington, Laura C. Sinclair, Kevin O. Knabe, William C. Swann, Nathan R. Newbury

Abstract

We present a comb calibrated frequency-modulated continuous wave (FMCW) LADAR system for absolute distance measurements to diffuse or specular surfaces. The FMCW LADAR uses a MEMS-based external cavity laser that is swept quasi-sinusoidally over 1 THz at a 1 kHz rate. The system simultaneously records the heterodyne FMCW LADAR signal and the instantaneous laser chirp of up to 3500 THz/sec, as measured against a free-running frequency comb (femtosecond fiber laser). Demodulation of the LADAR signal against the instantaneous laser chirp yields the range to the target with sub-millisecond update rates, bandwidth-limited 130-m resolution, precision as low as ~6 nm, and accuracy of ~ 100 ppb. The basic approach is compatible with operation at even faster update rates and with future chip-based coherent FMCW LADAR systems.
Citation
Optics Letters
Volume
38
Issue
12

Keywords

ranging, frequency modulated CW ladar, comb

Citation

Baumann, E. , Giorgetta, F. , Coddington, I. , Sinclair, L. , Knabe, K. , Swann, W. and Newbury, N. (2013), A comb-calibrated FMCW LADAR for absolute distance measurements, Optics Letters, [online], https://doi.org/10.1364/OL.38.002026 (Accessed April 17, 2024)
Created June 15, 2013, Updated November 10, 2018