High antenna directivity allows for high throughput transmission but also increases the exposure to electromagnetic field (EMF) of the end-users. Health regulations impose limitations on the incident power density, that generate a negative impact on network performance. In this work we focus at the slot-by-slot operations of a cellular Medium Access Control (MAC) scheduler to constrain the short-term EMF exposure upon real-time resource allocation, minimizing the impacts on network performance. We assume that the long-term EMF exposure is controlled by a proper outer-loop technique, that is not the object of this paper. Due to the minimal computational complexity allowed in MAC scheduling, existing solutions allowing practical implementation are few and focused at sub-optimal approaches curbing radio resource allocation. Our contribution is the derivation of a computationally efficient water-filling solution to allocate power and - then - resources, with a feasible integration of the necessary algorithms in the operations of a 5G MAC scheduler. We finally evaluate our proposal versus the prior art approaches with system level simulations with realistic modeling of physical and MAC level cellular procedures. We conclude that our proposal can control EMF with considerable less impact on network performance, making it a standout candidate for 5G and future 6G MAC scheduler implementations.

翻译：高天线方向性虽能实现高吞吐量传输，但也增加了终端用户的电磁场暴露水平。健康法规对入射功率密度施加限制，这将对网络性能产生负面影响。本研究聚焦蜂窝介质访问控制（MAC）调度器的逐时隙操作，在实时资源分配过程中约束短期电磁场暴露，从而最小化对网络性能的影响。我们假设长期电磁场暴露由适当的外环技术控制，这并非本文的研究对象。由于MAC调度允许的计算复杂度极低，现有可实现部署的解决方案很少，且多聚焦于次优的无线资源分配抑制方法。我们的贡献在于推导出一种计算高效的水填充算法，用于功率与资源的联合分配，并将必要算法可行地集成至5G MAC调度器操作中。最后，我们通过系统级仿真（采用物理层与MAC层蜂窝过程的实际建模）将所提方案与现有方法进行对比评估。结论表明，本方案在控制电磁场暴露的同时，对网络性能的影响显著降低，使其成为5G及未来6G MAC调度器实现中的突出候选方案。