MITSUBISHI ELECTRIC RESEARCH LABORATORIES http://www.merl.com Design Considerations and FPGA Implementation of a Wideband All-Digital Transmit Beamformer with 50% Fractional Bandwidth Sravan Kumar, Pulipati; Ma, Rui TR2020-078 June 24, 2020 Abstract In this work, we report design and implementation of an all-digital transmit phased array. The key design considerations have been reviewed including applications of multi-core DSM and wideband beamformer based on space-time theory. The built prototype of 8-element array using a commerical FPGA board demonstrated the feasibility of designing real-time wideband digital beamformer. The measured beam pattern for RF frequency of 2.5 GHz with 1.25 GHz bandwidth agreed well with simulation. To the authors’ knowledge, this fractional bandwidth of 50% is the widest one reported so far. This advances the state-of-the art in terms of fractional bandwidth by more than 40 times, which shows that all-digital transmitter is a very promising technology for next generation directional communications such as 5G and beyond. IEEE International Microwave Symposium (IMS) This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. Copying, reproduction, or republishing for any other purpose shall require a license with payment of fee to Mitsubishi Electric Research Laboratories, Inc. All rights reserved. Copyright c Mitsubishi Electric Research Laboratories, Inc., 2020 201 Broadway, Cambridge, Massachusetts 02139