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.

翻译：随着频率、带宽和阵列孔径的不断增加，波束斜视现象成为波束赋形中的严重障碍。每根天线单元配备真时延的全数字阵列是一种潜在解决方案，但需要在每个单元处进行下变频处理。本文证明，一旦射频链路的数量超过某个远低于天线单元数的阈值，混合阵列的性能便可与数字阵列基本相当。该结论具有鲁棒性，对于次优但极具吸引力的波束空间架构同样成立。