RADIOMETERS WITH CURVED VANES

Spectroscopy with Multichannel Correlation Radiometers

Correlation radiometers make true differential measurements in power with high accuracy and small systematic errors. This receiver architecture has been used in radio astronomy for measurements of continuum radiation for over 50 years; this article examines spectroscopy over broad bandwidths using correlation techniques. After general discussions of correlation and the choice of hybrid phase ex...

Hydrodynamic Lubrication of Sliding Vanes

Soil water infiltration observation with microwave radiometers

Experiments were conducted using truck-based microwave radiometers operating at 1.41(L-band) and 2.65-GHz (S-band) horizontal polarization to observe small plots during and following sprinkler irrigation. These experiments were conducted on a sandy loam soil in 1994 and a silt loam in 1995. Sandy loam soils typically have higher infiltration capabilities than clays, and in our studies, we were ...

Soil Moisture Sensing with Microwave Radiometers

Noise-Optimized Silicon Radiometers

This paper describes a new, experimentally verified, noise analysis and the design considerations of the dynamic characteristics of silicon radiometers. Transimpedance gain, loop gain, and voltage gain were optimized versus frequency for photodiode current meters measuring ac and dc optical radiation. Silicon radiometers with improved dynamic characteristics were built and tested. The frequency...