Advanced Microwave Sounding Unit-B (AMSU-B)
The Advanced Microwave Sounding Unit-B AMSU-B measures five microwave channels: One channel in the 89 GHz ‘window’ channel, one at 150 GHz and remaining three around the 183 GHz water vapor line (see Table for further details). The latter contributes sounding information on the water vapor profile in the troposphere and lower stratosphere (below about 10 km).
The scanning is from the sun side towards the darker side of the satellite path, that means away from the sun side of the spacecraft. That is a scan from west towards the east on an ascending node (PM).
One scan line is covered continuously in 2 2/3 of a second and contains 90 cells during one scan. The nominal horizontal resolution at nadir is 17 km.
The channel characteristics listed below are the scientific specification, formulated before the instruments were built. For actual characteristics, see the NOAA KLM Users Guide (section 3.4 and Appendix D)
AMSU-B Channel Characteristics
|Channel||Centre Frequency (GHz)||Bandwidth (MHz)||NeDT (K)||Calibration Accuracy (K)||pol. angle (°)|
|18||183.31 ± 1.00||500||1.1||1.0||nospec|
|19||183.31 ± 3.00||1000||1.0||1.0||nospec|
|20||190.31 ± 7.00||2000||1.2||1.0||90-q|