James Randa

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—We report on the characterization of blackbody target reflections as part of the recent progress on the development of brightness temperature standards for microwave remote sensing at the National Institute of Standards and Technology. The very low reflections from the blackbody targets used in airborne or satellite remote sensing systems present(More)
1. ABSTRACT Accurate characterization of the brightness temperature (T_B) of black-body targets used for calibrating microwave remote-sensing radiometers includes many inputs: antenna pattern and loss, target temperature, target emissivity, mechanical alignment, and radiometric T_B measurements calibrated against physical standards. Here we describe(More)
—The NIST Noise Project has developed the theoretical formalism and experimental methods for performing accurate noise-temperature measurements on a wafer. This report summarizes the theoretical formulation and describes the design, methods, and results of tests performed to verify our ability to measure on-wafer noise temperature. Several different(More)
—We report our recent progress toward the development of microwave brightness-temperature (BT) standards. As one of the crucial parameters, the target illumination efficiency (IE) was traditionally determined from the relative antenna pattern. We propose a measurement technique to extract the target IE solely by the use of passive radiometric measurements(More)
1. ABSTRACT After an interlude of several years, NIST has recently resumed efforts to develop a primary standard for microwave brightness temperature. The previous work is summarized in [1]. Currently the principal effort [2] is to develop a standard radiometer, traceable to fundamental primary noise standards, but we are also taking steps toward(More)
has developed the capability to measure noise parameters on a wafer in the 1–12.4-GHz range. We describe the measurement method and the uncertainty analysis and present results of measurements on a highly reflective transistor. Typical standard uncertainties are within the range of 20–25 K in T min , which is the minimum transistor noise temperature, and(More)