中文摘要：

在无线安全通信中，产生密钥并且保持其安全性是至关重要的。然而，由于无线信道的广播特性，在密钥分发阶段很容易受到各种攻击。利用多径信道的随机性是解决这一问题的可行方案。为了解决现有的基于物理层的密钥分配协议效率低并且依赖节点或者环境移动性的缺点，文献[12]提出了基于虚拟信道的快速密钥生成协议。该文通过理论证明：在多天线敌手的前提下，该协议不能在实现信息论安全的同时提高密钥生成率的理论上界。因此，该协议不是信息论安全的。

英文摘要：

It is vitally important to generate keys and keep them secret in secure wireless communications. Due to the broadcast nature of wireless channels, secret key distribution is more vulnerable to attacks in wireless communication. An ingenious solution is to generate secret keys by using the multipath channel as a source of common randomness. To address the problems that the existing physical-based protocols have low key generation rate and high reliance on mobile nodes or environments, a fast secret key generation protocol with virtual channel approach was proposed by HUANG and WANG for static wireless networks. In this paper, we show that, in the presence of an eavesdropper with multiple antennas, the scheme does not improve the theoretical upper bound of the key generation rate with information-theory security. Thus, the protocol is not information-theory security.