2.1 Introduction and Overview

The Airborne Multi-Spectral Scanner (AMSS) is a scanning spectrometer which flies on a Beechcraft-200 aircraft and provides spectral information similar to that which will be provided by the Global Imager (GLI) scheduled to be launched on the ADEOS-II platform in 1999.
          The AMSS spectrometer acquires high spatial resolution imagery in the range of 0.40 to 12.45 microns. Total of 59 spectral bands are available in this range. AMSS Record and Prcessing System was configured for each mission to record a pre-selected group of 46 signal No. in 14-bit resolution.
          The AMSS spectrometer is mated to a scanner sub-assembly which collects image data with an IFOV of 2.5 mrad, giving a ground resolution of 5 meters in 54 spectral bands and IFOV of 5.0 mrad, giving a ground resolution of 10 meters in 5 spectral bands from 2000 meters altitude , and a cross track scan width of +/- 40 degrees.

AMSS Instrument/Platform Specifications (1)

Wavelength Range /Center Wavelength	Bandwidth	IFOV	SNR,NEDT, at 50% albedo, 300k
400 - 800 nm	10-30 nm (variable)	2.5*1.25 mrad	23000-500
800 - 890 nm	10-30 nm (variable)	2.5*1.25 mrad	6000-1300
890 - 1000 nm	10-30 nm (variable)	2.5*1.25 mrad	1200-100
1050 nm	20 nm	5.0 mrad	120
1240 nm	20 nm	5.0 mrad	80
1650 nm	200nm	5.0 mrad	420
2215 nm	270nm	5.0 mrad	80
3.715 nm	0.33um	5.0 mrad	0.15
7.5 um	0.5 um	2.5 mrad	0.15
8.30 um	0.5 um	2.5 mrad	0.11
10.85 um	1.0 um	2.5 mrad	0.07
11.95 um	1.0 um	2.5 mrad	0.08

AMSS Instrument/Platform Specifications (2)

System Parameters	Scanning Method	Conical Scan
	Scan Rate	41.6 Hz
	Swath angle	+/-40 deg
	Dispersion Method	0.4-1.0 micrometer: 2grating
		1.0-12 micrometer: filter
	Instrument Mass	200 Kg
	Instrument Size	846*568*533(mm)
Data Processing	Quantization	14 bit
	Recording Media	1 VLDS
	Data Rate	4 MByte/s
	Max. No. of bands to be recorded	46
Flight Parameters	Platform	Beechcraft-200 aircraft
	Flight Altitude	1000 - 8000 m
	Ground Speed	150 kt
Visible Calibration	Integrating sphere on the ground
Infrared Calibration	Two black bodies on board