TY - JOUR

T1 - Measurements on Active Cold Loads for Radiometer Calibration

A1 - Søbjærg,Sten Schmidl

A1 - Skou,Niels

A1 - Balling,Jan E.

AU - Søbjærg,Sten Schmidl

AU - Skou,Niels

AU - Balling,Jan E.

PB - I E E E

PY - 2009

Y1 - 2009

N2 - Two semiconductor active cold loads (ACLs) to be used as cold references in spaceborne microwave radiometers have been developed. An X-band frequency was chosen, and the target noise temperature value was in the 50-100-K range. The ACLs are characterized in the operating temperature range of 0degC-50degC, and long-term stability is assessed. To this end, a test bed has been developed. This test bed is actually a stable radiometer, and its design and performance are discussed. The test setup is described, and test campaign results indicate output temperatures of 77 and 56 K for the two ACLs. The temperature sensitivity is slightly below 0.4 K/degC for the units, and long-term stability within 2 K/year is observed.

AB - Two semiconductor active cold loads (ACLs) to be used as cold references in spaceborne microwave radiometers have been developed. An X-band frequency was chosen, and the target noise temperature value was in the 50-100-K range. The ACLs are characterized in the operating temperature range of 0degC-50degC, and long-term stability is assessed. To this end, a test bed has been developed. This test bed is actually a stable radiometer, and its design and performance are discussed. The test setup is described, and test campaign results indicate output temperatures of 77 and 56 K for the two ACLs. The temperature sensitivity is slightly below 0.4 K/degC for the units, and long-term stability within 2 K/year is observed.

U2 - 10.1109/TGRS.2009.2017015

DO - 10.1109/TGRS.2009.2017015

JO - I E E E Transactions on Geoscience and Remote Sensing

JF - I E E E Transactions on Geoscience and Remote Sensing

SN - 0196-2892

IS - 9

VL - 47

SP - 3134

EP - 3139

ER -