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arXiv · 2310.07101

Hybrid Arrays: How Many RF Chains Are Required to Prevent Beam Squint?

Heedong Do·Namyoon Lee·Robert W. Heath Jr·Angel Lozano
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Abstract

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.

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Heedong Do, Namyoon Lee, Robert W. Heath Jr, Angel Lozano. 2023-10-11. Hybrid Arrays: How Many RF Chains Are Required to Prevent Beam Squint?. https://arxiv.org/abs/2310.07101

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