In this study, the authors investigate the secure coding issue for a wiretap channel model with fixed main channel and varying wiretap channel, by assuming that legitimate parties can obtain the wiretapping channel state information (CSI) with some delay. For the symmetric degraded delay CSI case, they present an explicit weak security scheme by constructing secure polar codes on a one-time pad chaining structure, and prove its weak security, reliability and capability of approaching the secrecy capacity for perfect CSI case with delay CSI assumption. Further for the symmetric no-degraded delay CSI case, they present a modified multi-block chaining structure in which the original subset of frozen bit is designed for conveying functional random bits securely. Then they combine this modified multi-block chaining structure with the weak security scheme to construct an explicit strong security polar coding scheme, and prove its strong security, reliability and also the capability of approaching the secrecy capacity for perfect CSI case with delay CSI assumption. At last, they carry out simulations to prove the performance of both secure schemes.

中文翻译：

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延迟窃听信息的安全极性编码

在这项研究中，作者通过假设合法方可以获得一定延迟而获得窃听信道状态信息（CSI），从而研究了具有固定主信道和变化窃听信道的窃听信道模型的安全编码问题。对于对称降级的延迟CSI情况，他们通过在一次性填充链结构上构造安全极性代码，提出了一种显式的弱安全方案，并证明了其弱安全性，可靠性以及在具有延迟CSI的情况下达到完美CSI情况的保密能力的能力。假设。此外，对于对称的不降级延迟CSI情况，他们提出了一种改进的多块链接结构，其中冻结位的原始子集被设计用于安全地传输功能随机位。然后，他们将这种改进的多块链接结构与弱安全方案相结合，构造出显式的强安全极性编码方案，并证明了其强安全性，可靠性以及在具有延迟CSI假设的情况下达到理想CSI情况的保密能力。最后，他们进行仿真以证明两种安全方案的性能。