SSMIS


The Special Sensor Microwave Imager / Sounder is a 24-channel, 21-frequency, linearly polarized passive microwave radiometer system. The instrument is flown on board the United States Air Force Defense Meteorological Satellite Program F-16, F-17, F-18 and F-19 satellites, which became operational in November 2005, March 2008 March 2016 and May 2016, respectively. It is the successor to the Special Sensor Microwave/Imager. The SSMIS on the F19 satellite stopped producing useful data in February 2016.

Instrument characteristics

The SSMIS sensor is a passive conically scanning microwave radiometer that combines and extends the current imaging and sounding capabilities of three previously separate DMSP microwave sensors: the SSM/T-1 temperature sounder, the SSMI/T- 2 moisture sounder, and the SSM/I. The SSMIS instrument measures microwave energy at 24 discrete frequencies from 19 to 183 GHz with a swath width of 1700 km.
The first SSMIS was launched aboard the DMSP-16 satellite on 18 October 2003.
Due to a manufacturing mistake, the polarization for the channels at 50.3, 52.8, 53.6, 54.4 and 55.5 of the first unit of SSMIS was reversed. Those five channels detect the vertical polarization rather than the Horizontal polarization detected by the successive units of SSMIS.
Frequency PolarizationAlong-track resolution Cross-track resolution Spatial sampling Instrument noise
19.35horizontal734745x740.35
19.35vertical734745x740.35
22.235vertical734745x740.45
37.0horizontal413128x450.22
37.0vertical413128x450.22
50.3horizontal17.627.337.50.34
52.8horizontal17.627.337.50.32
53.596horizontal17.627.337.50.33
54.4horizontal17.627.337.50.33
55.5horizontal17.627.337.50.34
57.29right circular17.627.337.50.41
59.4right circular17.627.337.50.40
63.283248 ± 0.285271right circular17.627.3752.7
60.792668 ± 0.357892right circular17.627.3752.7
60.792668 ± 0.357892 ± 0.002right circular17.627.3751.9
60.792668 ± 0.357892 ± 0.0055right circular17.627.3751.3
60.792668 ± 0.357892 ± 0.016right circular17.627.3750.8
60.792668 ± 0.357892 ± 0.050right circular17.627.3750.9
91.665horizontal141313x160.19
91.665vertical141313x160.19
150horizontal141313x160.53
183.311 ± 1horizontal141313x160.38
183.311 ± 3horizontal141313x160.39
183.311 ± 6.6horizontal141313x160.56