Improving secret key generation for wireless communications in FDD mode

Abstract

Summary Most recent research on channel‐based key generation oriented to time division duplex system because the channel reciprocity feature is applied directly for secret key generation. Most of commercial cellular systems depend on frequency division duplex (FDD) systems. In this paper, we investigate the impact of uplink and downlink of FDD systems for the generation of shared secret keys between two parties in the presents of passive eavesdropper. In addition, we are considering improving the rate of the secret key for wireless communication in FDD mode. The main idea is to use the fading coefficient of the channels between the relay and other parties as an additional random common source for the secret key generation. Also, explore the using of channel estimation techniques to reduce the channel training sequence and study its effect on the generation of shared key for wireless communications in FDD mode. We derive the upper bound of the generated shared key rate for four scenarios and give numerical examples to reveal the performance of our suggested improvement approaches.

Cooperative Key Establishment Protocol for Full-Duplex Relay Systems

“…The overall channel from the source to the destination via the relay, in amplifying and forwarding (A & F) systems, is two Gaussian channels with features considerably different from a typical cellular channel [12]. In our novel work [13], we developed a key extraction protocol based on the non-reciprocity of FD channel. As a result, one can design a scheme that can exploit the randomness provided by round-trip FD link between two terminals.…”

“…As a result, one can design a scheme that can exploit the randomness provided by round-trip FD link between two terminals. In this paper, we exploit this fact and extend our work in [13] to the case of cooperation communication systems. In this paper, we regard the channel estimation stage, of key extraction from FD relay channel, to prove the feasibility of establishing a common randomness source based on the FD wireless relaying channel.…”

A secret key establishment in frequency division duplex communication systems under active attacker

“…For illustration, when the two nodes attempt to estimate the channel status, the adversary transmits interfering signals to minimize the accuracy of the channel estimation process. In this paper, we extend the capability of the adversary from the passive case introduced in our recent work …”