複素チャネル係数に基づく無線秘密鍵共有における複数地点盗聴による秘密鍵容量の低下

Hideichi Sasaoka, Hisato Iwai

Published Jul 31, 2022• 0 citations

Abstract

Secret key agreement based on radio propagation characteristics attracts attention as a kind of the wireless physical layer security. However, there are few studies on drop of the secret key capacity by multiple spot eavesdropping. This paper derived theoretical formula of the secret key capacity in secret key agreement based on the complex channel coefficient. This paper also derived theoretical formula of the leakage information by multiple spot eavesdropping and showed that leakage information increased with the increase of the eavesdropping spot number. Validity of these theoretical formulas was confirmed by computer simulation. Then, this paper calculated the coefficient of correlation of the channel coefficient in the simple propagation environment and evaluated security of secret key agreement by calculating leakage information for multiple spot eavesdropping.

DOI: 10.14988/00029078

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