Comparative Analysis of Noise-Reduction Filters for Low-cost Radio Telescope Data

^1,4 Centre of Excellence in Astronomical Studies, Institute of Engineering & Management, University of Engineering and Management, Kolkata, India
^2,3 Department of Robotics & AI, Institute of Engineering & Management, University of Engineering and Management, Kolkata, India

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 29 May 2026

Abstract

In observational astronomy, the correct extraction of solar radio signals is the major requirement, but such data obtained through low-budget radio telescopes are often deteriorated by strong narrowband interference. The radio telescope systems, which are usually designed with easily available components such as parabolic dish antennas, connecting cables, low-cost satellite meters, and spectrum analyzers, have inadequate shielding for signals and hence remain extremely susceptible to additional noise. Regarding the above-mentioned realistic constraints, the presented study attempts a number of widely used signal filtering methods, including lowpass, Chebyshev, Gaussian, median, bandstop, and notch filters, with simulation-based investigations using software and comparison of filters was carried out by employing MSE, SNR, and correlation coefficient as evaluation parameters. Based on the presented analysis, it was found that the notch filter showed the best performance among the above-mentioned approaches, since it attained an SNR value of 46.10 dB while offering the minimum MSE of 0.100035 along with a correlation coefficient which is very close to unity (0.9992). These values demonstrate that the notch filter acts effectively to suppress the undesired interference while preserving the intrinsic characteristics of the radio signal coming from the Sun. It is a unique approach to develop a less expensive and efficient filtering technique for low-budget radio telescope operating within urban or semi-urban areas with generally higher levels of interference.