While state-of-the-art cryogenic receiver front end technology becomes more reliable and cost effective, the extent of actual performance gains still remains questionable and ill-defined. In order to support quantitative insight into cryogenic system deployment, this investigation explores the system performance characteristics of a generalized receiver model as a function of component temperature, antenna position (ground or space-based), antenna orientation and operational frequency. Specifically, the advantages offered by cryogenic relative to conventional components are analytically formulated and quantitatively assessed for a representative satellite up/down link antenna/receiver system. The extent to which signals can be usefully received is determined by the noise levels (natural and man-made) received by the antenna and those generated within the receiver. In order to characterize the upper bound of system performance, only natural sources of noise are investigated at the exclusion of potential man-made sources. Moreover, the magnitude of these noise contributions are observed to vary with frequency and are empirically characterized over a broad spectra from HF to mm wave. A general RF front end model is formulated to support a fully parametric analysis. The focus of this investigation is to provide a fundamental understanding of the real benefits that may be derived from cryogenic system implementation.