This paper proposes a novel physical beam sharing system to use few radio-frequency (RF) chains to support more users. The concept of beam sharing is to design a beam pattern to simultaneously benefit all users. In this proposed system, every user can receive a number of data streams equal to the number of RF chains at the base station (BS) and achieve full multiplexing gain. A special design example is that the BS can support multiple users simultaneously even with only one RF chain. As a result, the computational and hardware costs of the BS can be significantly reduced due to the decreased RF chains in deploying a dense communications network. We first derive beamforming designs for this proposed system in a MISO channel with one data stream. Then, the results are further extended to MIMO channels with multiple data streams. Simulation results show that the proposed schemes with the derived solutions outperform conventional systems in several interested parameter settings, and have advantages in terms of fairness and complexity compared with NOMA (non-orthogonal multiple access) systems. Moreover, we also implemented 28 GHz hardware platforms with an 8×88 \times 8 antenna array to verify the feasibility and advantages of the proposed schemes as well as measure the resulting beam patterns. The over-the-air (OTA) testings validate the concept of the proposed physical beam sharing and show that it outperforms conventional physical beamforming schemes.

中文翻译：

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物理波束共享多用户系统：波束成形设计和 OTA 测试


本文提出了一种新颖的物理波束共享系统，使用少量射频（RF）链来支持更多用户。波束共享的概念是设计一种波束图案以同时使所有用户受益。在该系统中，每个用户都可以接收与基站（BS）射频链数量相等的数据流，并实现完全复用增益。一个特殊的设计示例是，即使只有一条射频链，BS 也可以同时支持多个用户。因此，由于部署密集通信网络时射频链的减少，基站的计算和硬件成本可以显着降低。我们首先在具有一个数据流的 MISO 通道中为该系统推导出波束成形设计。然后，将结果进一步扩展到具有多个数据流的 MIMO 信道。仿真结果表明，所提出的方案及其导出的解决方案在几个感兴趣的参数设置上优于传统系统，并且与NOMA（非正交多址）系统相比在公平性和复杂性方面具有优势。此外，我们还实现了具有 8×88 × 8 天线阵列的 28 GHz 硬件平台，以验证所提出方案的可行性和优势，并测量所得的波束方向图。空中（OTA）测试验证了所提出的物理波束共享的概念，并表明它优于传统的物理波束形成方案。