Toward an optical fiber spectral radiometer for surface reflectance measurements

Vicarious calibration of future space-based spectral imagers will require ground-based measurements of much higher accuracy and precision than current field instruments support. A promising new technology is the use of a multi-mode fiber as the source of dispersion, replacing a grating. It has recently been demonstrated that the wavelength dependent speckle pattern present at the output of a multimode fiber may be exploited to recover the spectrum of the illuminating source, potentially enabling very compact and stable instruments. In this paper, we review our development of a performance model to assess the prospects for developing a field spectral radiometer based on this concept.