Equivalent External Noise Temperature of Time-Varying Receivers
<|reference_start|>Equivalent External Noise Temperature of Time-Varying Receivers: The equivalent external noise temperature of time-varying antennas is studied using the concept of cross-frequency effective aperture, which quantifies the intermodulation conversion of external noise across the frequency spectrum into a receiver's operational bandwidth. The theoretical tools for this approach are laid out following the classical method for describing external noise temperature of linear time-invariant antennas, with generalizations made along the way to capture the effects of time-varying components or materials. The results demonstrate the specific ways that a time-varying system's noise characteristics are dependent on its cross-frequency effective aperture and the broadband noise environment. The general theory is applied to several examples, including abstract models of hypothetical systems, antennas integrated with parametric amplification, and time-modulated arrays.<|reference_end|>
@article{schab2024equivalent,
    title={Equivalent External Noise Temperature of Time-Varying Receivers},
    author={Kurt Schab and K.C. Kerby-Patel},
    journal={arXiv preprint arXiv:2405.20471},
    year={2024},
    archivePrefix={arXiv},
    eprint={2405.20471},
    primaryClass={eess.SY cs.SY}
}