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2.2 Hyperspectral sensors<br />

Chapter 2 41<br />

Nowadays, hyperspectral sensors are increasing their importance in remote sensing<br />

studies. ESA Chris-Proba 11 and Hyperion 12 were the first satellite missions<br />

dedicated to this sensor. However, their spatial resolution (30 meters for Hyperion,<br />

from 18 to 30 for Chris-Proba) cannot be considered as ―Very High Resolution‖,<br />

therefore no useful for the purposes of the study.<br />

For this reason, it has been decided to use airborne hyperspectral sensors, which<br />

combines very high spatial resolution with several contiguous bands.<br />

2.2.1 AHS<br />

The Airborne Hyperspectral Scanner (AHS) is an imaging line-scanner radiometer,<br />

installed on a CASA-212 200 series aircraft owned by Spain's National Institute for<br />

Aerospace Technology (INTA) 13 .<br />

The AHS instrument (Fig. 2.5), with a whiskbroom linescanner, acquires images in<br />

80 spectral bands covering the visible and near infrared (VNIR), short wave<br />

infrared (SWIR), mid-infrared (MIR), and thermal infrared (TIR) spectral ranges<br />

(Table 1), having a digitisation accuracy of 12 bits.<br />

With its wide spectra, AHS has been used for several earth observation topics, as<br />

thermography [206] and agriculture [207].<br />

11<br />

ESA Chris Proba home page: http://earth.esa.int/missions/thirdpartymission/proba.html<br />

12<br />

Nasa Hyperion Instrument: http://eo1.gsfc.nasa.gov/Technology/Hyperion.html<br />

13<br />

The INTA AHS system<br />

http://bo.eufar.net/document/publi/124901161346543eefc58cf:SPIE_RS05_INTA_5978-56.pdf

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