Ambient radio frequency (RF) energy harvesting (EH) technology is key to realize self-sustainable, always-on, low-power, massive Internet of Things networks. Typically, rigid (non-adaptable to channel fluctuations) multi-antenna receive architectures are proposed to support reliable EH operation. Herein, we introduce a dynamic RF combining architecture for ambient RF EH use cases, and exemplify the attainable performance gains via three simple mechanisms, namely, brute force (BF), sequential testing (ST) and codebook based (CB). Among the proposed mechanisms, BF demands the highest power consumption, while CB requires the highest-resolution phase shifters, thus tipping the scales in favor of ST. Finally, we show that the performance gains of ST over a rigid RF combining scheme increase with the number of receive antennas and energy transmitters' deployment density.

中文翻译：

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用于多天线环境能量收集的动态射频组合

环境射频 (RF) 能量收集 (EH) 技术是实现自我可持续、永远在线、低功耗、大规模物联网网络的关键。通常，建议使用刚性（不适应信道波动）多天线接收架构来支持可靠的 EH 操作。在此，我们为环境射频 EH 用例引入了一种动态射频组合架构，并通过三种简单的机制来举例说明可实现的性能提升，即蛮力 (BF)、顺序测试 (ST) 和基于码本的 (CB)。在提议的机制中，BF 需要最高的功耗，而 CB 需要最高分辨率的移相器，因此倾向于 ST。最后，