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We present three new design solutions—centimeter-band radiometric units and the design of each radio unit. We demonstrate the development of an uncooled tuned receiver based on this unit which is meant for operating in the total-power radiometer mode. In practice the parameters of the new radiometric units are currently close to the limit values for uncooled microwave amplifiers. The new radiometers are designed to be used for continuum observations at the RATAN-600 Radio Telescope. This approach is universal and promising to be applied at any radio telescope. [ABSTRACT FROM AUTHOR]

We describe the development of the tools and methods of 4.7-GHz band observations on RATAN-600 radio telescope and present a new design solution—a radiometric unit, and the development of an uncooled tuned receiver based on this unit and meant for operating in the “total power” radiometer mode.We discuss the design of the radio unit and the specificities of the radiometer design.We demonstrate the possibility of conducting observations in the total power radiometer mode at the theoretical sensitivity on time scales up to 10 seconds. The sensitivity of such a radiometer remains higher than that of a Dicke radiometer on time scales up to 100 seconds. [ABSTRACT FROM AUTHOR]

We report the experimental results of a study of the sources of 1/ f type noise (hereafter referred to as 1/ f-type noise for the sake of brevity) in a total power radiometer. We find this noise to have two main sources in the radiometer: microwave amplifiers and the square-law diode detector with a Schottky barrier. We present methods for a substantial reduction of 1/ f-type noise, which allow total power radiometer measurements to be performed with nominal sensitivity on time scales of up to 10 seconds. The sensitivity of the total power radiometer on time scales up to 100 seconds remains higher than that of a Dicke switched radiometer. [ABSTRACT FROM AUTHOR]