FPGA based Digital Backend System for Low Frequency Radio Observations

Abstract

Radio Astronomy involves digital systems for processing and analyzing the celestial radio signals received by the radio antennas. In recent days, Field Programmable Gate Arrays (FPGAs) are used for digital signal processing because of their advantages over earlier systems in many respects. In this thesis we are focusing on the implementation of the digital backend on an FPGA based system. The basic instrument covered is a 1-bit digital correlator. We also discuss the aspects of telemetry of the correlation data to a PC. The observations using this correlator setup and the inferences from them for various sampling rates, bandwidths etc. are compared to optimize the system performance. This helps in improving the observing capabilities of the radio backend receivers presently working at the Gauribidanur Radio Observatory.