Radio Telescope Design for the Observation of 21 Cm Neutral Hydrogen Emission

The detection of the global 21 cm hydrogen signal from the early Universe presents significant challenges due to the extremely faint nature of the signal compared to foreground emissions. This project focuses on the design and analysis of a radio antenna system developed for the REACH (Radio Experiment for the Analysis of Cosmic Hydrogen) initiative. By leveraging a quantitative, figure-of-merit-driven methodology, we explore how antenna geometry, impedance matching, and beam chromaticity affect the system’s ability to distinguish the cosmological signal from foreground noise. Various candidate antenna designs, including wide-beam dipoles and high-gain structures, are evaluated through electromagnetic simulations and mock detection pipelines. We assess their performance based on spectral smoothness, calibration feasibility, and compatibility with Bayesian data analysis techniques. The final design prioritizes simplicity and spectral stability while maintaining a broad operational bandwidth, aiming to enhance the robustness and reliability of global 21 cm hydrogen signal detection.