Radiometric Calibration of a Dual-Wavelength, Full-Waveform Terrestrial Lidar

Zhan Li; David L B Jupp; Alan H Strahler; Crystal B Schaaf; Glenn Howe; Kuravi Hewawasam; Ewan S Douglas; Supriya Chakrabarti; Timothy A Cook; Ian Paynter; Edward J Saenz; Michael Schaefer

doi:10.3390/s16030313

Radiometric Calibration of a Dual-Wavelength, Full-Waveform Terrestrial Lidar

Sensors (Basel). 2016 Mar 2;16(3):313. doi: 10.3390/s16030313.

Authors

Zhan Li^{1

2}, David L B Jupp³, Alan H Strahler⁴, Crystal B Schaaf⁵, Glenn Howe⁶, Kuravi Hewawasam⁷, Ewan S Douglas⁸, Supriya Chakrabarti⁹, Timothy A Cook¹⁰, Ian Paynter¹¹, Edward J Saenz¹², Michael Schaefer^{13

14}

Affiliations

¹ Department of Earth and Environment, Boston University, 675 Commonwealth Avenue, Boston, MA 02215, USA. zhanli86@bu.edu.
² School for the Environment, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. zhanli86@bu.edu.
³ CSIRO Land & Water, GPO Box 1666, Canberra, ACT 2601, Australia. David.Jupp@csiro.au.
⁴ Department of Earth and Environment, Boston University, 675 Commonwealth Avenue, Boston, MA 02215, USA. alan@bu.edu.
⁵ School for the Environment, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. Crystal.Schaaf@umb.edu.
⁶ Department of Physics and Applied Physics, University of Massachusetts Lowell, 600 Suffolk Street, Lowell, MA 01854, USA. ghowephysics@gmail.com.
⁷ Department of Physics and Applied Physics, University of Massachusetts Lowell, 600 Suffolk Street, Lowell, MA 01854, USA. Kuravi_Hewawasam@student.uml.edu.
⁸ Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, USA. douglase@bu.edu.
⁹ Department of Physics and Applied Physics, University of Massachusetts Lowell, 600 Suffolk Street, Lowell, MA 01854, USA. Supriya_Chakrabarti@uml.edu.
¹⁰ Department of Physics and Applied Physics, University of Massachusetts Lowell, 600 Suffolk Street, Lowell, MA 01854, USA. Timothy_Cook@uml.edu.
¹¹ School for the Environment, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. Ian.Paynter@umb.edu.
¹² School for the Environment, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. Edward.Saenz@umb.edu.
¹³ CSIRO Land & Water, GPO Box 1666, Canberra, ACT 2601, Australia. michael.schaefer@csiro.au.
¹⁴ Precision Agriculture Research Group, School of Science and Technology, University of New England, Armidale, NSW 2351, Australia. michael.schaefer@csiro.au.

Abstract

Radiometric calibration of the Dual-Wavelength Echidna(®) Lidar (DWEL), a full-waveform terrestrial laser scanner with two simultaneously-pulsing infrared lasers at 1064 nm and 1548 nm, provides accurate dual-wavelength apparent reflectance (ρ(app)), a physically-defined value that is related to the radiative and structural characteristics of scanned targets and independent of range and instrument optics and electronics. The errors of ρ(app) are 8.1% for 1064 nm and 6.4% for 1548 nm. A sensitivity analysis shows that ρ(app) error is dominated by range errors at near ranges, but by lidar intensity errors at far ranges. Our semi-empirical model for radiometric calibration combines a generalized logistic function to explicitly model telescopic effects due to defocusing of return signals at near range with a negative exponential function to model the fall-off of return intensity with range. Accurate values of ρ(app) from the radiometric calibration improve the quantification of vegetation structure, facilitate the comparison and coupling of lidar datasets from different instruments, campaigns or wavelengths and advance the utilization of bi- and multi-spectral information added to 3D scans by novel spectral lidars.

Keywords: DWEL; dual-wavelength lidar; full-waveform lidar; radiometric calibration; terrestrial lidar; vegetation structure.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.