Project Title:

High Sensitivity Active Cavity Radiometer

08.02-0071
High Sensitivity Active Cavity Radiometer
The Radiometrics Corporation
PO Box 215
Altadena, CA 91001
Richard C. Willson
GSFC -- NAS5-30288

Abstract:

	 The Activity Cavity Radiometer Irradiance Monitor experiment on the Solar Maximum
Mission has demonstrated the state-of-the-art accuracy and precision for solar observations
of active cavity radiometer (ACR) sensors in space flight. The design and operational
advantages of the solar ACR sensors have been successfully applied to wide and medium
field of view earth-viewing sensors on the Earth Radiation Budget (ERB) experiments.
If the sensitivity of the solar ACR sensors were increased by between one and two
orders of magnitude, the advantages could be applied to the narrow field of view
observations of future ERB-type experiments, replacing the inaccurate and unreliable
scanning systems in current use. The objective of this project was to modify the
ACR solar sensor cavity design and electronics to achieve such an improvement in
performance without sacrificing accuracy.
	During Phase I (not complete at this writing), the cavity of a new detector was
designed and procured, the electronic boards for the detector and the electronics
for testing were fabricated, and the software for test and analysis was developed.

Potential Commercial Application:

Potential Commercial Application: Applications would include any optical radiation
measurement tasks that require state-of-the-art accuracy and precision at the irradiance
levels corresponding to 1 to 100 percent of the total solar irradiance (1368 watts/square
meter).