Teaching and Research Opportunities in Solar Noise Measurements Using Low-Cost Satellite TV Receiving Systems

Solar radio emissions from the photosphere and corona represent a well-known source of interference for satellite communication systems, particularly during Sun transit events, when the Sun aligns with the line of sight between a ground receiver and a geostationary satellite. While these phenomena are typically studied using large, high-gain research antennas, they also offer a valuable opportunity for higher education, demonstrating how meaningful space physics measurements can be carried out using simple and widely available instrumentation.

This contribution shows that reasonably accurate measurements of solar noise can be obtained using commercial satellite TV receiving systems, such as Direct-To-Home (DTH) Ku-band antennas and low-cost receivers, commonly employed for satellite broadcasting. These systems are inexpensive, easy to deploy, and familiar to students, making them particularly suitable for educational activities that bridge undergraduate teaching, laboratory work, and applied research.

The work is based on long-term measurements originally collected in the context of rainfall opportunistic sensing (ROS) experiments, which continuously monitor the received signal strength from geostationary broadcast satellites using small parabolic dishes (0.6–1.5 m diameter). During Sun transit events, these datasets naturally include characteristic signal-to-noise ratio (SNR) degradations caused by solar radio emission entering the antenna beam. By exploiting these events, students can learn how to extract physical information—such as equivalent solar noise temperature—directly from real-world measurements.

A key educational aspect addressed in this study is the role of antenna beam geometry. Commercial Ku-band antennas have beamwidths of approximately 1.5–3°, significantly larger than the apparent solar disk (~0.53°). As a consequence, the received signal integrates emissions from the entire solar disk and part of the surrounding corona. This effect is discussed and compared, for reference, with measurements from high-gain X-band antennas of NASA’s Deep Space Network, which provide much narrower beams and spatially selective observations. Such comparisons help students understand fundamental concepts in antenna theory, radiometry, and measurement uncertainty.

Experimental results from a multi-year campaign (2018–2023), conducted in northern Tuscany using a 0.8 m dish pointed at a GEO broadcast satellite, are presented as an example of how Sun transit measurements can be incorporated into teaching laboratories and student projects. The apparent solar trajectory across the antenna beam is reconstructed using solar ephemerides, enabling a direct connection between theoretical models and observed data.

Overall, this contribution demonstrates that low-cost satellite TV equipment can serve as an effective educational and research tool for introducing students to solar radio physics, satellite communications, and experimental data analysis, fostering hands-on learning while producing scientifically meaningful results.

Acknowledgements: This work was supported by the following projects: Space It Up, funded by Italian Space Agency (ASI) and the Italian Ministry of University and Research (MUR) – Contract 2024-5-E.0 - CUP I53D24000060005; FoReLab (Departments of Excellence), funded by MUR.