We propose a novel advantage distillation strategy for physical layer-based secret-key-agreement (SKA). We consider a scenario where Alice and Bob aim at extracting a common bit sequence, which should remain secret to Eve, by quantizing a random number obtained from measurements at their communication channel. We propose an asymmetric advantage distillation protocol with two novel features: i) Alice quantizes her measurement and sends partial information on it over an authenticated public side channel, and ii) Bob quantizes his measurement by exploiting the partial information. The partial information on the position of the measurement in the quantization interval and its sharing allows Bob to obtain a quantized value closer to that of Alice. Both strategies increase the lower bound of the secret key rate.

翻译：我们提出一种新的物理层秘密密钥协商（SKA）优势蒸馏策略。考虑Alice和Bob通过对通信信道测量获得的随机数进行量化，以提取对Eve保持秘密的公共比特序列的场景。我们提出一种非对称优势蒸馏协议，具有两个新颖特性：i) Alice对其测量值进行量化，并通过认证的公共侧信道发送部分信息；ii) Bob利用该部分信息对其测量值进行量化。关于测量值在量化区间内位置的部分信息及其共享，使得Bob能够获得更接近Alice的量化值。这两种策略均提高了秘密密钥速率的下界。