This article introduces a power-efficient and low-cost CMOS 28-GHz phased-array beamformer supporting fifth-generation (5G) dual-polarized multiple-in-multiple-out (MIMO) (DP-MIMO) operation. To improve the cross-polarization (cross-pol.) isolation degraded by the antennas and propagation, a power-efficient analog-assisted cross-pol. leakage cancellation technique is implemented. After the high-accuracy cancellation, more than 41.3-dB cross-pol. isolation is maintained along with the transmitter array to the receiver array. The element-beamformer in this work adopts the compact neutralized bi-directional architecture featuring a minimized manufacturing cost. The proposed beamformer achieves 22% per path TX-mode efficiency and a 4.9-dB RX-mode noise figure. The required on-chip area for the beamformer is only 0.48 mm ² . In over-the-air measurement, a 64-element dual-polarized phased-array module achieves 52.2-dBm saturated effective isotropic radiated power (EIRP). The 5G standard-compliant OFDMA-mode modulated signals of up to 256-QAM could be supported by the 64-element modules. With the help of the cross-pol. leakage cancellation technique, the proposed array module realizes improved DP-MIMO EVMs even under severe polarization coupling and rotation conditions. The measured DP-MIMO EVMs are 3.4% in both 64-QAM and 256-QAM. The consumed power per beamformer path is 186 mW in the TX mode and 88 mW in the RX mode.

中文翻译：

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5G MIMO系统中利用交叉极化泄漏消除的CMOS双极化相控阵波束形成器

本文介绍了一种支持第五代（5G）双极化多进多出（MIMO）（DP-MIMO）操作的省电，低成本CMOS 28 GHz相控阵波束形成器。为了改善由于天线和传播而导致的交叉极化（cross-pol。）隔离问题，采用了高能效的模拟辅助cross-pol。实施了泄漏消除技术。高精度消除后，交叉极化超过41.3 dB。与发送器阵列到接收器阵列一起保持隔离。这项工作中的单元波束形成器采用紧凑的中和双向架构，具有最小化的制造成本。拟议的波束形成器可实现每路径22％的TX模式效率和4.9 dB RX模式噪声系数。波束形成器所需的片上面积仅为0.48 mm ² 。在空中测量中，由64个元件组成的双极化相控阵模块可实现52.2 dBm的饱和有效各向同性辐射功率（EIRP）。64个元素的模块可以支持高达256-QAM的符合5G标准的OFDMA模式调制信号。在交叉警察的帮助下。泄漏消除技术，即使在严重的偏振耦合和旋转条件下，所提出的阵列模块也可以实现改进的DP-MIMO EVM。在64-QAM和256-QAM中，测得的DP-MIMO EVM均为3.4％。在TX模式下，每个波束形成器路径的功耗为186 mW，在RX模式下为88 mW。