Digital Phased Arrays: Challenges and Opportunities

TLDR

Digital beamforming promises unprecedented flexibility and dynamic range by digitizing signals at each array element, yet it faces significant data‑processing and transceiver‑complexity challenges. The paper surveys the trade‑off spaces of DBF systems and highlights emerging concepts for distributed beamforming and processing in both fixed and adaptive arrays. It discusses calibration techniques that can lessen the reliance on heavy beamforming computations.

Abstract

Digital beamforming (DBF) has long been heralded as the next frontier in phased array technology, and not without reason. The digitization of transmit and receive signals at the element level opens the door to new processing and beamforming schemes and promises to deliver maximum flexibility and unprecedented dynamic range in large systems. However, it is not without inherent technological risks and practical challenges associated with the amount of data to process and the use of less sophisticated transceivers. This paper provides broad overviews of several interrelated aspects of the resulting DBF trade spaces for these systems. In particular, emerging concepts are highlighted for the roles and interconnection of distributed beamforming/processing for fixed and adaptive beamforming. These are then related to digital array calibration mechanisms that can potentially reduce the need for data- and processing-intensive beamforming algorithms.