Underlay spectrum sharing addresses spectrum scarcity but imposes constraints on the interference the secondary system causes to the primary receiver. For a secondary transmitter that is subject to the stochastic and general interference-outage constraint and the peak transmit power constraint, we present a novel joint antenna selection and power adaptation rule. It addresses the twin goals of improving the spectral efficiency and reducing the power consumed of an underlay secondary system with low hardware complexity and cost. We prove that the rule maximizes the energy-efficiency (EE) of the secondary system. Its form differs from all other rules considered in the literature. We then present an insightful geometrical characterization of the optimal power of the selected antenna in terms of the channel gains within the secondary system and between the secondary and primary systems. Our approach leads to several special cases, which are themselves novel, and novel analytical insights about the performance and structure of the optimal rule. We also present an iterative subgradient-based algorithm and a simpler non-iterative bound-based algorithm to compute the rule’s parameters. The rule achieves a markedly higher EE compared to conventional approaches, and serves as a new fundamental benchmark for antenna selection in underlay spectrum sharing.

中文翻译：

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干扰中断约束底层频谱共享的最佳节能天线选择和功率适应

底层频谱共享解决了频谱稀缺问题，但限制了辅助系统对主接收器造成的干扰。对于受随机和一般干扰中断约束和峰值发射功率约束的辅助发射机，我们提出了一种新的联合天线选择和功率自适应规则。它以低硬件复杂性和成本解决了提高频谱效率和降低底层二次系统功耗的双重目标。我们证明了该规则最大化了二次系统的能量效率（EE）。它的形式不同于文献中考虑的所有其他规则。然后，我们根据辅助系统内以及辅助系统和主系统之间的信道增益，对所选天线的最佳功率进行了深入的几何表征。我们的方法导致了几种特殊情况，这些情况本身是新颖的，并且是关于最优规则的性能和结构的新颖的分析见解。我们还提出了一种基于迭代次梯度的算法和一种更简单的基于非迭代边界的算法来计算规则的参数。与传统方法相比，该规则实现了明显更高的 EE，并作为底层频谱共享中天线选择的新基本基准。以及关于最优规则的性能和结构的新颖分析见解。我们还提出了一种基于迭代次梯度的算法和一种更简单的基于非迭代边界的算法来计算规则的参数。与传统方法相比，该规则实现了明显更高的 EE，并作为底层频谱共享中天线选择的新基本基准。以及关于最优规则的性能和结构的新颖分析见解。我们还提出了一种基于迭代次梯度的算法和一种更简单的基于非迭代边界的算法来计算规则的参数。与传统方法相比，该规则实现了明显更高的 EE，并作为底层频谱共享中天线选择的新基本基准。