Secret key generation (SKG) between authenticated devices is a pivotal task for secure communications. Diffie-Hellman (DH) is de-facto standard but not post-quantum secure. In this paper, we shall invent and analyze a new security primitive that is specifically designed for WPAN. For WPAN, wireless channel-based SKG has been proposed but was not widely deployed due to its critical dependence on the channel's entropy which is uncontrollable. We formulate a different approach: We still exploit channel properties but mainly hinge on the reciprocity of the wireless channel and not on the channel's entropy. The radio advantage comes from the use of full duplex communication. We show that in this situation both legitimate parties can agree on a common secret key even without ever probing the channel at all. At the core is a new bisparse blind deconvolution scheme for which we prove correctness and information-theoretic, i.e. perfect, security. We show that, ultimately, a secret key can be extracted and give a lower bound for the number of secret key bits which is then verified by experiments.

翻译：认证设备之间的密钥生成（SKG）是安全通信的关键任务。Diffie-Hellman（DH）是事实标准，但并非后量子安全。本文将发明并分析一种专为WPAN设计的新型安全原语。针对WPAN领域，基于无线信道的SKG方案已被提出，但由于其严重依赖不可控的信道熵而未能广泛部署。我们提出一种不同方法：仍利用信道特性，但主要依赖无线信道的互易性而非信道熵。其无线电优势源于全双工通信的运用。我们证明，在此场景下，即使完全不进行信道探测，合法双方也能协商出共享密钥。其核心是一种新型双稀疏盲反卷积方案，我们证明了该方案的正确性及信息论意义上的完美安全性。最终，我们展示了密钥的提取方法，并给出了密钥比特数的下界，该下界已通过实验验证。