Steering Beams and Nulling Interference in a Radio Telescope Array
Rizchel Masong, Perry Neil Fernandez, Paul Keenan Butt

De La Salle University, University of Philippines Visayas, De La Salle Araneta University

Abstract

Radio astronomy observations are increasingly threatened by signal interference, especially at sensitive frequencies like the 1.4 GHz hydrogen line. Phased array antennas, which combine signals from many small antennas, offer a flexible way to solve this by precisely shaping their listening direction. This project presents the design and simulation of a digital control system for such an array, created to both track celestial objects and cancel interference at the same time. The system calculates the ideal settings for each antenna to point the main listening beam at an astronomical target while creating targeted ^dead spots,^ or nulls, in the direction of interference sources like satellites or terrestrial transmitters.

We used computer simulations to model the array^s performance, focusing on the rapid calculations needed to scan the beam across the sky smoothly. A key feature is a null-placement algorithm that works together with the main beam steering, allowing the array to react to new interference sources without losing track of the observation target. Simulations show the system can accurately steer the main beam while creating very deep nulls that reduce unwanted signals. This approach promises to significantly improve the clarity of astronomical signals significantly, boosting the performance and data quality of modern radio telescopes.

Keywords: Radio Astronomy, Physics, Instrumentation

Topic: Instrumentation in Astronomy