A New Multichannel Parallel Real-time FFT Algorithm for a Solar Radio Observation System Based on FPGA. (1st March 2022)

• Record Type: Journal Article
• Authors: Zhang, Yuan Y.; Zhang, Lei; Shang, Zi Q.; Su, Yan R.; Wu, Zhao; Yan, Fa B.
• Is Part Of: Publications of the Astronomical Society of the Pacific. Volume 134:Number 1033(2022)
• Publication Date: 2022-03-01
• Subjects: Astronomy -- Periodicals; Astronomy; Periodicals; Periodicals; 520.5
• DOI: 10.1088/1538-3873/ac5212
• Languages: English
• ISSNs: 0004-6280

Abstract

Abstract: The real-time fast Fourier transform (FFT) is the essential algorithm for signal processing in a solar radio receiver. However, field-programmable gate array (FPGA) computation resources have become the limitation of real-time processing of signals with increasing time and spectral resolutions. It is necessary to design a real-time parallel FFT algorithm with reduced resource occupation in the development of future receiving systems. In this paper, we developed a multichannel parallel FFT algorithm named the multichannel parallel real-time fast Fourier transform (MPR-FFT), which can greatly reduce FPGA resource occupation while increasing the real-time processing speed. In this algorithm, the 4 L simultaneous N -point FFTs are first converted into L simultaneous 4 N -point FFTs. Fusion processing is then performed to obtain the 4 ∗ L ∗ N -point spectrum. This method has been used in developing a solar radio spectrometer, which works in the frequency range of 0.5–15 GHz in the Chashan Observatory. In this spectrometer, 16 channel MPR-FFT with 8k-point data is realized in a Xilinx UltraScale KU115 FPGA. The MPR-FFT algorithm reduced the computational resources to a large extent compared to the Cooley-Tukey-based parallel FFT method; for instance, the Look-Up-Table, Look-Up-Table RAM, Flip-Flop, and Digital Signal Process slices were reduced by 37%, 50%, 17%, and 2.48%, respectively. Although the MPR-FFT consumes 14 block RAM resources more than the Cooley-Tukey-based parallel FFT, the MPR-FFT algorithm presents an overall reduction in resource usage.