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arXiv · 0804.2940

Secret Key Agreement by Soft-decision of Signals in Gaussian Maurer's Model

Masashi Naito·Shun Watanabe·Ryutaroh Matsumoto·Tomohiko Uyematsu
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Abstract

We consider the problem of secret key agreement in Gaussian Maurer's Model. In Gaussian Maurer's model, legitimate receivers, Alice and Bob, and a wire-tapper, Eve, receive signals randomly generated by a satellite through three independent memoryless Gaussian channels respectively. Then Alice and Bob generate a common secret key from their received signals. In this model, we propose a protocol for generating a common secret key by using the result of soft-decision of Alice and Bob's received signals. Then, we calculate a lower bound on the secret key rate in our proposed protocol. As a result of comparison with the protocol that only uses hard-decision, we found that the higher rate is obtained by using our protocol.

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Masashi Naito, Shun Watanabe, Ryutaroh Matsumoto, Tomohiko Uyematsu. 2008-04-18. Secret Key Agreement by Soft-decision of Signals in Gaussian Maurer's Model. https://doi.org/10.1587/transfun.e92.a.525

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