US 4,864,309 A · Microwave radiometer

Abstract

A microwave radiometer is formed of a set of frequency scanning antennas disposed parallel to each other and connected by a common microwave feeder. Signals of individual ones of the antennas are translated to different intermediate frequencies such that differences between the intermediate frequencies are proportional to baseline spacings between pairs of antennas of nested interferometers. A correlator containing parallel delay lines and a set of multiplier channels coupled to paired taps of the delay lines receives signals at the intermediate frequencies to produce a set of correlation signals. A two-dimensional Fourier transformation is applied to the correlation output signals to provide the power spectral density of microwave radiation incident upon the array of antennas.

Claims12

Dependent claims

A microwave radiometer comprising:

an array of antennas;
a common microwave feeder;
translation means connecting each of said antennas to said common feeder, said translation means offsetting a carrier frequency of incoming radiation incident at each of said antennas to an intermediate frequency, said translation means outputting a different intermediate frequency for each antenna to provide a set of intermediate signals at specific intermediate frequencies for the respective antennas, said feeder summing together said intermediate signals to provide a sum signal;
means for amplifying the sum signal;
correlator means coupled via said amplifying means to said feeder for providing an autocorrelation of the sum signal;
and
signal processing means coupled to said correlator means for outputting a measure of power of the incoming radiation.

4 more elements

Dependencies are inferred from the claim text.

Microwave radiometer

Life of this patent

Microwave radiometer

Life of this patent

Abstract

Claims12