Sensors: Image Processing Library
| AVIRIS |
- Spatial resolution 20 m x 20 m
- Spectral coverage 380 nm- 2500 nm
- Spectral range 224 bands
- 1 milliradian Instantaneous Field Of View (IFOV, one sample), calibrated to within 0.1 mrad
- 30 degrees total field of view (full 614 samples)
- 12 Hz scanning rate
- "Whisk broom" scanning
- 10 bit data encoding through 1994, 12 bit from 1995.
- 17 Mbps data rate through 1994, 20.4 Mbps from 1995.
- 10 nm nominal channel bandwith, calibrated to within 1 nm
The AVIRIS Concept
The AVIRIS instrument contains 224 different detectors, each with a wavelength sensitive range (also known as spectral bandwidth) of approximately10 nanometers (nm), allowing it to cover the entire range between 380 nm and 2500 nm. When the data from each detector is plotted on a graph, it yields a spectrum. Comparing the resulting spectrum with those of known substances reveals information about the composition of the area being viewed by the instrument.AVIRIS uses a scanning mirror to sweep back and forth ("whisk broom" fashion), producing 614 pixels for the 224 detectors each scan. Each pixel produced by the instrument covers an approximately 20 meter square area on the ground (with some overlap between pixels), thus yielding a ground swath about 11 kilometers wide.
The ground data is recorded on board the instrument along with navigation and engineering data and the readings from the AVIRIS on-board calibrator. When all of this data is processed and stored on the ground, it yields approximately 140 Megabytes (MB) for every 512 scans (or lines) of data. Each 512 line set of data is called a "scene", and corresponds to an area about 10km long on the ground.
Spectral Band and Radiometric Corrections
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1992 Spectral Calibration File
1992 Radiometric Calibration File
1993 Spectral Calibration File (05/17 - 07/25)
1993 Spectral Calibration File (08/08 - 09/27)
1993 Radiometric Calibration File (05/17 - 07/25)
1993 Radiometric Calibration File (08/08 - 09/27)
1994 Spectral Calibration File
1994 Radiometric Calibration File
1995 Spectral Calibration File
1995 Radiometric Calibration File
1996 Spectral Calibration File
1996 Radiometric Calibration File
Sensors
Last Modified: Wed Apr 14, 1999
CSR/TSGC Team Web