Abstract:
In this paper, we describe in detail the
prototyping of a mini radiometer for spectral data
measurements. It is based on three main parts: -1- an
RGB + near-infrared leds for the emitted light and a
photodiode for the reflected light. -2- An 8-bit
microcontroller for automatic data acquisition,
calibrating and storing. -3- A user interface with small
keypad + LCD display. An optional serial link interface is
also provided for a compatible PC/Windows platform,
with an open source C++ application software, in order
to handle and deal with the mass of data collected. This
instrument is useful for measuring the spectral
reflectance of different land covers, in the visible and
near-infrared wavelengths, to allow the construction of a
characteristic curve named spectral signature of the
object. The study of spectral signatures for different types
of surfaces such as water, bare ground or vegetation (to
name a few) allows their automatic identification by
remote sensing, as done, for instance, by the NOAA
satellite system, using the AVHRR (Advanced very High
Resolution Radiometer) data sensor of the freely
distributed HRPT (High Resolution Picture Transmission)
images.
