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Proximity effects in the calibration of microwave radiometers



Ronald C. Wittmann, Amanda Cox, Randy Direen


Microwave, total-power radiometers are calibrated by observing sources of known brightness temperature. Free-space calibrations are usually performed assuming far-field interactions, although the actual calibration source may be well into the near-field region of the radiometer antenna. Here, we simulate the free-space coupling between radiometer and calibration target to explore the potential contribution of proximity effects to measurement uncertainty.
Proceedings Title
Proc., Antenna Meas. Tech. Asoc. Symp.
Conference Dates
October 30-November 4, 2005
Conference Location
Newport, RI, USA
Conference Title
Antenna Measurement Techniques Association


calibration, microwave, near-field gain, radiometer, remote sensing, uncertainty analysis


Wittmann, R. , Cox, A. and Direen, R. (2005), Proximity effects in the calibration of microwave radiometers, Proc., Antenna Meas. Tech. Asoc. Symp., Newport, RI, USA (Accessed June 21, 2024)


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Created September 30, 2005, Updated October 12, 2021