With increasing frequencies, bandwidths, and array apertures, the phenomenon of beam squint arises as a serious impairment to beamforming. Fully digital arrays with true time delay per antenna element are a potential solution, but they require downconversion at each element. This paper shows that hybrid arrays can perform essentially as well as digital arrays once the number of radio-frequency chains exceeds a certain threshold that is far below the number of elements. The result is robust, holding also for suboptimum but highly appealing beamspace architectures.
@article{arxiv.2310.07101,
title = {Hybrid Arrays: How Many RF Chains Are Required to Prevent Beam Squint?},
author = {Heedong Do and Namyoon Lee and Robert W. Heath and Angel Lozano},
journal= {arXiv preprint arXiv:2310.07101},
year = {2023}
}