A High-Throughput Oversampled Polyphase Filter Bank Using Vivado HLS and PYNQ on a RFSoC

Jennifer Pearl Smith,J I Bailey,Benjamin A Mazin,John Tuthill,Leandro Stefanazzi,Ken Treptow,Gustavo Cancelo

doi:10.1109/ojcas.2020.3041208

Abstract

Many digital signal processing applications require a channelizer capable of moving sections of the incoming spectrum to baseband quickly and efficiently with minimal spectral leakage and signal distortion. We report the design and implementation of a 4 GHz, 4096-branch, 8-tap, 2/1 oversampled polyphase channelizer implemented on a Xilinx RFSoC. The open-source design consists of only IP cores created using Vivado HLS (C++) and IP cores available in Vivado HLx and System Generator versions 2019.1+. The channelizer was tested using a PYNQ overlay and Jupyter Notebook (Python) hosted on the RFSoC embedded CPU. The design uses 24% of the LUTs, 9% of the DSP48s, and 11% of the BRAMs on the ZCU111 RFSoC evaluation board and meets timing constraints at 512 MHz. The oversampled polyphase channelizer suppresses spectral image components below -60 dB. This design provides the first example of an oversampled polyphase channelizer running on a system on a chip architecture created without direct use of hardware description language. The presented approach leverages high-level design tools and includes source code which can be readily adapted by other researchers and development teams without the need for specialist knowledge in high-performance FPGA design.

Highlights

L ARGE data bandwidths are an important theme underpinning the development of new technologies including 5G/6G devices for wireless communications [1], [2], real-time video processing for self-driving cars [3], and microwave device arrays for quantum computing and astronomy [4]–[7]
This work hopes to serve as a similar guide for how to create an efficient oversampled polyphase filter bank channelizer which is introduced
This design provides the first example of an ultra-wideband, high-performance oversampled polyphase filter bank channelizer implemented on modern architecture using open-source code which readily allows customization and re-use by other groups

Summary

INTRODUCTION

L ARGE data bandwidths are an important theme underpinning the development of new technologies including 5G/6G devices for wireless communications [1], [2], real-time video processing for self-driving cars [3], and microwave device arrays for quantum computing and astronomy [4]–[7]. This work hopes to serve as a similar guide for how to create an efficient oversampled polyphase filter bank channelizer which is introduced This design provides the first example of an ultra-wideband, high-performance oversampled polyphase filter bank channelizer implemented on modern architecture using open-source code which readily allows customization and re-use by other groups. OVERSAMPLED POLYPHASE FILTER BANK Oversampled polyphase filter banks (OPFB) are an extension of the PFB algorithm where data is recycled, effectively implementing overlapping channels while still achieving the required stopband rejection for each channel This oversampled structure is required for applications demanding uniform response over wide bandwidths containing many separate channels such as a spectrometer, applications looking to utilize the full spectrum including 5G/6G wireless, and applications multiplexing large numbers of microwave resonators as is done in quantum computing and astronomy. As the first group to make our oversampled polyphase filter bank source code freely available, we hope the results of our efforts will be adapted, reused, and built upon for future technological endeavors

CHANNELIZER DESIGN

IMPLEMENTATION

HARDWARE TESTING AND VERIFICATION

Findings

CONCLUSION