Achievable data rates in wireless systems rely heavily on the available channel state information (CSI) throughout the network. However, feedback links, which provide this information, are scarce, unreliable, and subject to security threats. In this work, we study the impact of having intermittent feedback links on the capacity region of the canonical two-user erasure broadcast channels. In our model, at any time instant, each receiver broadcasts its CSI, and at any other node, this information either becomes available with unit delay or gets erased. For this setting, we develop a new set of outer bounds to capture the intermittent nature of the feedback links. These outer bounds depend on the probability that the CSI from both receivers are erased at the transmitter. In particular, if at any time, the CSI from at least one of the two receivers is available at the other two nodes, then the outer-bounds match the capacity with global delayed CSI. We also provide capacity-achieving transmission strategies under certain scenarios, and we establish a connection between this problem and Blind Index Coding with feedback.

中文翻译：

---

擦除带有间歇反馈的广播频道


无线系统中可实现的数据速率在很大程度上依赖于整个网络中可用的信道状态信息 (CSI)。然而，提供此信息的反馈链接很少、不可靠，并且容易受到安全威胁。在这项工作中，我们研究了间歇性反馈链路对规范两用户擦除广播信道容量区域的影响。在我们的模型中，在任何时刻，每个接收器都会广播其 CSI，并且在任何其他节点，该信息要么以单位延迟变得可用，要么被删除。对于这种设置，我们开发了一组新的外部边界来捕获反馈链接的间歇性性质。这些外部边界取决于来自两个接收器的 CSI 在发射器处被擦除的概率。特别地，如果在任何时间，来自两个接收器中的至少一个的CSI在另外两个节点处可用，则外界将容量与全局延迟CSI相匹配。我们还提供了某些场景下实现容量的传输策略，并通过反馈建立了该问题与盲索引编码之间的联系。