Inter-Site Fluctuation Mechanics and Phase-Noise Convolutions in RF/Microwave Mixers and Local Oscillators (LO)
Year: 2026
Type: preprint
Abstract: Heterodyne receivers represent the cornerstone of radio astronomy instrumentation, enabling high-resolution spectral line observations (such as 1420 MHz neutral hydrogen line surveys and deep astronomical continuum measurements) across ground-based installations and professional observatories alike. Operating by frequency-converting incoming RF sky signals down to intermediate frequencies (IF) via non-linear mixing elements (Schottky diodes, SIS junctions, or active transistor mixers) pumped by a high-spectral-purity Local Oscillator (LO), heterodyne systems are exquisitely sensitive to phase jitter and excess low-frequency noise. In this work, we extend our first-principles inter-site fluctuation mechanics and tripartite noise hierarchy—previously established for cryogenic transistors, Transition-Edge Sensors (TES), and Kinetic Inductance Detectors (KIDs)—to the non-linear electrodynamic transport regime of RF/microwave mixers and LO chains. We formulate a rigorous stochastic master equation coupling quantum zero-point phase dispersion, amorphous barrier tunneling, and large-signal pumping dynamics. We derive the exact conversion of intrinsic inter-site resistance fluctuations and LO phase noise sidebands through the non-linear conductance matrix of the mixer, establishing how upconversion and downconversion mechanisms generate anomalous low-frequency excess flicker noise. Finally, we outline a high-performance MATLAB simulation architecture designed to model conversion loss, noise temperature contributions, and spectral exponent transitions across operating regimes, providing instrument designers and radio astronomers with an uncompromising theoretical foundation.
Author: Glenn-Anderson, James
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225568391