Characterization of background sky noise and system temperature in BURT observations of 3C 433 with nanotechnology-enhanced receiver systems

Abstract

An empirical characterization of background sky noise and the corresponding antenna noise temperature measured by the Baghdad University Radio Telescope (BURT) is presented for a six-month observation campaign targeting the radio galaxy 3C 433 (December 2024 – June 2025). A fixed noise threshold of −92 dBm is applied to isolate sub-threshold signals, and all data are processed using a MATLAB-based workflow to compute average noise power and equivalent antenna temperature. The analysis yielded a mean system temperature of approximately 90 K, with observed variations of ±10 K across the campaign. Seasonal trends are evident, with lower noise levels (~80 K) during winter and higher levels (~100 K) during spring, primarily driven by atmospheric humidity and ionospheric electron content. A detailed breakdown of noise contributions indicates that receiver and feed noise (15–20 K) and ground spillover (5–10 K) are the dominant controllable components, while sky background (5–8 K) and ionospheric effects (2–5 K) represent fundamental environmental limits. The stability of the results confirms consistent receiver performance with no significant long-term drift. In addition to empirical analysis, a nanotechnology-based enhancement model is evaluated through simulation. The results indicate that nano-engineered low-noise amplifiers, metamaterial feed designs, and nano-coatings could reduce system temperature to approximately 70–85 K, corresponding to an overall improvement of about 10–15%. These findings demonstrate that, while environmental noise remains unavoidable, targeted improvements in receiver and antenna subsystems provide a practical pathway to enhancing sensitivity in small radio telescopes.