MiRS: ATMS Overview

The Advanced Technology Microwave Sounder (ATMS), a cross-track scanner with 22 channels, provides sounding observations needed to retrieve profiles of atmospheric temperature and moisture for civilian operational weather forecasting as well as continuity of these measurements for climate monitoring purposes. Like the long heritage of its predecessors, ATMS combines all the channels of the preceding AMSU-A1, AMSU-A2, and AMSU-B sensors into a single package with considerable savings in mass, power, and volume.

Like the long heritage of its predecessors, ATMS is a cross-track scanner, but ATMS combines all the channels of the preceding AMSU-A1, AMSU-A2, and AMSU-B sensors into a single package with considerable savings in mass, power, and volume. 22 channels in bands from 23 GHz through 183 GHz are included. ATMS will fly on the NPP and JPSS missions. Note that there are likely to be subtle differences between the NPP version of ATMS and the JPSS version(s) of ATMS.

Principal challenges/advantages of ATMS: (1) Reduced size/power relative to predecessor AMSU; (2)1/4 volume, 1/2 mass, 1/2 power; (3) Scan drive mechanism, MMIC technology; (4) Improved spatial coverage (no gaps between swaths); (5) Nyquist spatial sampling of temperature bands: Improved information content relative to AMSU-A.

ATMS Channel Characteristics
Channel	Center Freq.(GHz)	Polarization	Max Bandwidth(GHz)	Temperature Sensitivity(K) NEΔT
1	23.8	V	0.27	0.9
2	31.4	V	0.18	0.9
3	50.3	H	0.18	1.20
4	51.76	H	0.40	0.75
5	52.8	H	0.40	0.75
6	53.596±0.115	H	0.17	0.75
7	54.40	H	0.40	0.75
8	54.94	H	0.40	0.75
9	55.50	H	0.33	0.75
10	57.2903	H	0.33	0.75
11	57.2903±0.115	H	0.078	1.20
12	57.2903	H	0.036	1.20
13	57.2903±0.322	H	0.016	1.50
14	57.2903±0.322±0.010	H	0.008	2.40
15	57.2903±0.322±0.004	H	0.003	3.60
16	87-91(88.20)	V	2.0	0.5
17	165.5	H	3.0	0.6
18	183.31±7	H	2.0	0.8
19	183.31±4.5	H	2.0	0.8
20	183.31±3	H	1.0	0.8
21	183.31±1.8	H	1.0	0.8
22	183.31±1.0	H	0.5	0.9

Source: NASA NPP Site ( npp.gsfc.nasa.gov/atms.html )