Privacy-aware laser wireless power transfer for aerial multi-access edge computing: a Colonel Blotto game approach

This paper studies the integration of laser-beamed wireless power transfer (WPT) into high-altitude platform (HAP) aided multi-access edge computing (MEC) systems for the HAP-connected aerial user equipments (AUEs). By discretizing the three-dimensional coverage space of the HAP, we present a multi-tier tile grid-based spatial structure to provide the aerial locations in the form of tile grids to AUEs for laser charging. We identify a new privacy vulnerability caused by the openness during the WPT signaling transfer in the presence of a terrestrial adversary, which is able to launch the attacks by distributing the false tile grids to the AUEs. To address this vulnerability and enhance the location privacy of AUEs, we then propose a Colonel Blotto (CB) game framework to formulate the competitive tile grid allocation problem for the HAP and the adversary. The attack-defense interaction between the adversary and the HAP as a defender in their tile grid allocations to the AUEs is formulated as a CB game, which models the competition of two players for limited resources over multiple battlefields. Moreover, we derive the mixed-strategy Nash equilibria of the game for both symmetric and asymmetric tile grids between two players. Simulation results show that the proposed framework significantly outperforms the design baselines with a given privacy protection level in terms of system-wide expected total utilities.