Advances in microwave digital radiometry

The increasing availability of discrete and integrated high-speed digital logic has enabled the advancement of microwave digital radiometry for Earth science applications. The first digital radiometers were used for autocorrelation spectroscopy with bandwidths of a few megahertz. Current digital radiometers operate with bandwidths of hundreds-of-megahertz. The applications of digital radiometers have been extended to include polarimetry, interferometry, and total power radiometry. Future technology development opportunities include increasing the speed and lowering the power of digital processors, track-and-hold circuits, and analog-to-digital converters.