Title: Truth-Telling Mechanism for Secure Two-Way Relay Communications with Energy-Harvesting Revenue,
Abstract: This paper brings the novel idea of paying the utility to the winning agents
in terms of some physical entity in cooperative communications. Our setting is
a secret two-way communication channel where two transmitters exchange
information in the presence of an eavesdropper. The relays are selected from a
set of interested parties such that the secrecy sum rate is maximized. In
return, the selected relay nodes' energy harvesting requirements will be
fulfilled up to a certain threshold through their own payoff so that they have
the natural incentive to be selected and involved in the communication.
However, relays may exaggerate their private information in order to improve
their chance to be selected. Our objective is to develop a mechanism for relay
selection that enforces them to reveal the truth since otherwise they may be
penalized. We also propose a joint cooperative relay beamforming and transmit
power optimization scheme based on an alternating optimization approach. Note
that the problem is highly non-convex since the objective function appears as a
product of three correlated Rayleigh quotients. While a common practice in the
existing literature is to optimize the relay beamforming vector for given
transmit power via rank relaxation, we propose a second-order cone programming
(SOCP)-based approach in this paper which requires a significantly lower
computational task. The performance of the incentive control mechanism and the
optimization algorithm has been evaluated through numerical simulations.