5G and Wi-Fi systems are embracing coexistence in the unlicensed portions of the 5–7 GHz bands recently allocated by FCC to support the increasing data rate demands for the growing number of wireless users. To achieve fair and effective spectrum sharing, both 5G and Wi-Fi rely on carrier sensing for medium access. However, differences in sensing thresholds create an unfair advantage for 5G nodes, as they access the medium more aggressively and degrade the data rate and latency of Wi-Fi users. We first demonstrate how an adversary can stealthily exploit this unfairness to further reduce the spectrum occupancy of Wi-Fi nodes, effectively denying Wi-Fi services. Accordingly, in this paper, we propose a novel implicit channel coordination (ICC) approach to both mitigate starvation attacks and improve spectrum access fairness under practical considerations like noise and strong adversaries who try to circumvent our technique. In ICC, Wi-Fi access points (APs) influence 5G gNBs into choosing a precoding matrix that nearly nullifies 5G downlink signals at the APs, enabling concurrent gNB and AP transmissions while accounting for a hidden terminal problem this creates. We theoretically analyze and show that our ICC mitigates novel attacks we have identified, and experimentally demonstrate on a USRP testbed its resilience against starvation attacks. Our design outperforms prior work by achieving an overall 30% higher data rate of the 5G and Wi-Fi coexistence system, 3x improvement in spectrum access fairness, and 1.5x in system capacity, all while conforming with the latency requirements of 5G.

中文翻译：

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使用稳健的隐式通道协调实现公平、安全的 5G 和 Wi-Fi 共存


5G 和 Wi-Fi 系统正在 FCC 最近分配的 5-7 GHz 频段的免许可部分共存，以满足不断增长的无线用户数量不断增长的数据速率需求。为了实现公平有效的频谱共享，5G 和 Wi-Fi 都依赖载波侦听来进行介质访问。然而，传感阈值的差异为 5G 节点带来了不公平的优势，因为它们更积极地访问介质，并降低了 Wi-Fi 用户的数据速率和延迟。我们首先演示对手如何秘密地利用这种不公平性来进一步减少 Wi-Fi 节点的频谱占用，从而有效地拒绝 Wi-Fi 服务。因此，在本文中，我们提出了一种新颖的隐式信道协调（ICC）方法，可以在噪声和试图规避我们技术的强大对手等实际考虑因素下减轻饥饿攻击并提高频谱访问公平性。在 ICC 中，Wi-Fi 接入点 (AP) 影响 5G gNB 选择一个几乎使 AP 处的 5G 下行链路信号无效的预编码矩阵，从而实现并发 gNB 和 AP 传输，同时解决由此产生的隐藏终端问题。我们从理论上分析并证明我们的 ICC 可以缓解我们发现的新型攻击，并在 USRP 测试平台上通过实验证明其对饥饿攻击的恢复能力。我们的设计优于之前的工作，使 5G 和 Wi-Fi 共存系统的整体数据速率提高了 30%，频谱访问公平性提高了 3 倍，系统容量提高了 1.5 倍，同时符合 5G 的延迟要求。