Beamforming Techniques and Interference Mitigation Using a Multiple Feed Array for Radio Astronomy

BEAMFORMING TECHNIQUES AND INTERFERENCE MITIGATION USING A MULTIPLE FEED ARRAY FOR RADIO ASTRONOMY Chad K. Hansen Department of Electrical and Computer Engineering Master of Science Radio frequency interference has become a large problem to radio astronomers. This thesis proposes the idea that radio frequency interference can be mitigated using a phased array feed in conjunction with a large reflector. A phased array feed would allow radio astronomers to observe fainter signals than is currently possible, while at the same time enabling rapid sky surveys. A phased array feed was designed and simulated, and sensitivity optimization was performed on the array feed. It was shown that higher sensitivity can be achieved using a 7-element phased array feed than with a conventional waveguide feed. Simulations were ran using RFI mitigation algorithms on the array to show that interference cancellation can, in principle, be performed using a phased array feed. In addition to these simulations, improvements were made to a previously designed RF receiver so that radio astronomy observations could be made and interference mitigation algorithms tested on a receiver platform.

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