The U.S. has adopted four power regimes for opera tion in the shared unlicensed 6 GHz band -- standard power (SP), low-power indoor (LPI), geofenced variable power (GVP), and very low power (VLP) -- with maximum permitted EIRP levels of 36 dBm, 30 dBm, 24 dBm, and 14 dBm, respectively. Although these regimes are primarily intended to protect incumbent services, their heterogeneous transmit power levels also introduce additional coexistence challenges within 6 GHz Wi-Fi networks. In this paper, we develop an ns-3 Wi-Fi 6E/802.11ax coexistence testbed to study coexistence under heterogeneous power regimes and to provide a reproducible simulation methodology. To the best of our knowledge, prior work has not specifically examined self-coexistence issues within 6 GHz Wi-Fi networks. We evaluate two coexistence scenarios: one in which both the LPI AP and the SP AP are indoors, and another in which the LPI AP is indoors while the SP AP is outdoors. Results are compared against an indoor LPI--LPI baseline when applicable. Our findings show that: (i) the presence of an indoor SP AP can significantly degrade the goodput of an LPI AP; (ii) channel bandwidth is a key factor in determining the extent of SP-to-LPI impact, with the degradation being most severe at 20 MHz and partially alleviated at 160 MHz; (iii) physical blockage between outdoor SP and LPI APs improves fairness; and (iv) BSS coloring does not necessarily improve fairness in mixed-regime deployments. The simulation framework can be extended to study coexistence between Wi-Fi and cellular systems, as recently proposed by Ofcom in the U.K.

翻译：美国在共享非授权6GHz频段中采用了四种功率体制——标准功率（SP）、低功率室内（LPI）、地理围栏可变功率（GVP）和极低功率（VLP），其最大允许EIRP水平分别为36 dBm、30 dBm、24 dBm和14 dBm。尽管这些体制主要旨在保护既有服务，但其异构发射功率水平也给6GHz Wi-Fi网络内部带来了额外的共存挑战。本文构建了一个ns-3 Wi-Fi 6E/802.11ax共存测试平台，用于研究异构功率体制下的共存问题，并提供可复现的仿真方法。据我们所知，此前的研究并未专门探讨6GHz Wi-Fi网络中的自共存问题。我们评估了两种共存场景：一种场景中LPI接入点（AP）与SP接入点均位于室内，另一种场景中LPI接入点位于室内而SP接入点位于室外。在适用情况下，结果与室内LPI-LPI基线进行对比。研究结果表明：（i）室内SP接入点的存在会显著降低LPI接入点的吞吐量；（ii）信道带宽是决定SP对LPI影响程度的关键因素，在20 MHz带宽下性能下降最为严重，而在160 MHz带宽下得到部分缓解；（iii）室外SP接入点与室内LPI接入点之间的物理遮挡可改善公平性；（iv）在混合体制部署场景中，BSS着色并不必然提升公平性。该仿真框架可扩展用于研究Wi-Fi与蜂窝系统之间的共存问题，正如英国通信管理局（Ofcom）近期所提议的那样。