Development of Pulsar Digital Backend Based on RFSoC

Abstract

Radio Frequency System on Chip (RFSoC) offers great potential for implementing a complete next generation signal processing system on a single board for radio astronomy. We designed a pulsar digital backend system based on the ZCU111 board. The system uses RFSoC technology to implement digitization, channelization, correlation and high-speed data transmission in the Xilinx ZU28DR device. We have evaluated the performance of the eight 12-bit RF-ADCs, which are integrated in RFSoC, with the maximum sampling rate of 4.096 GSPS. The RF-ADC sampling frequency, channel bandwidth and time resolution can be configured dynamically in our designed system. To verify the system performance, we deployed the RFSoC board on the Nanshan 26 m radio telescope and observed the pulsar signal with a frequency resolution of 1 MHz and time resolution of 64 μs. In the observation test, we obtained pulsar profiles with high signal-to-noise ratio and accurately searched the DM values. The experimental results show that the performance of RF-ADCs, FPGA and CPU cores in RFSoC is sufficient for radio astronomy signal processing applications.