The impressive growth of wireless data networks has recently led to increased attention to the issue of electromagnetic pollution. Specific absorption rates and incident power densities have become popular indicators for measuring electromagnetic field (EMF) exposure. This paper tackles the problem of power control in user-centric cell-free massive multiple-input-multiple-output (CF-mMIMO) systems under EMF constraints. Specifically, the power allocation maximizing the minimum data rate across users is derived for both the uplink and the downlink under EMF constraints. The developed solution is also applied to a cellular mMIMO system and compared to other benchmark strategies. Simulation results prove that EMF safety restrictions can be easily met without jeopardizing the minimum data rate, that the CF-mMIMO outperforms the multi-cell massive MIMO deployment, and that the proposed power control strategy greatly improves the system fairness.

翻译：无线数据网络的迅猛发展近期引发了人们对电磁污染问题的广泛关注。比吸收率和入射功率密度已成为衡量电磁场暴露的常用指标。本文针对电磁场约束下以用户为中心的无小区大规模多输入多输出系统中的功率控制问题展开研究。具体而言，在电磁场约束条件下，推导了上行链路和下行链路中最大化用户最小数据速率的功率分配方案。该解决方案还被应用于蜂窝大规模MIMO系统，并与其它基准策略进行了比较。仿真结果表明：电磁安全限制可在不牺牲最小数据速率的前提下轻松满足；无小区大规模MIMO性能优于多小区大规模MIMO部署；所提功率控制策略显著提升了系统公平性。