Introducing Hierarchy in Energy Games

In this work we introduce hierarchy in wireless networks that can be modeled by a decentralized multiple access channel and for which energy-efficiency is the main performance index. In these networks users are free to choose their power control strategy to selfishly maximize their energy-efficiency. Specifically, we introduce hierarchy in two different ways: 1. Assuming single-user decoding at the receiver, we investigate a Stackelberg formulation of the game where one user is the leader whereas the other users are assumed to be able to react to the leader's decisions; 2. Assuming neither leader nor followers among the users, we introduce hierarchy by assuming successive interference cancellation at the receiver. It is shown that introducing a certain degree of hierarchy in non-cooperative power control games not only improves the individual energy efficiency of all the users but can also be a way of insuring the existence of a non-saturated equilibrium and reaching a desired trade-off between the global network performance at the equilibrium and the requested amount of signaling. In this respect, the way of measuring the global performance of an energy-efficient network is shown to be a critical issue.Comment: Accepted for publication in IEEE Trans. on Wireless Communication

Introducing Hierarchy in Energy-Efficient Power Control Games

We consider a multiple access channel where the users choose their best power control strategy in order to sel¯shly max- imize their energy-e±ciency. To increase the utilities with respect to the classical non-cooperative game, we introduce hierarchy in two ways. On the one hand, assuming single- user decoding at the receiver, we investigate a Stackelberg formulation of the game where one user is the leader. On the other hand, assuming neither leader nor followers among the users, we introduce hierarchy by using successive in- terference cancelation at the receiver. For both cases, we study the existence and uniqueness of an equilibrium and compare the individual performance obtained in the hierar- chical game with that obtained in the non-cooperative game. An exhaustive comparative analysis of the two games is also conducted. In order to optimize the choice of the leader in the Stackelberg formulation (with single user decoding) and that of the decoding order (in the non-cooperative game with successive interference cancelation), we study two measures of global energy-e±ciency for the network and discussions are provided for each case

Introducing Hierarchy in Energy-Efficient Power Control Games

We consider a multiple access channel where the users choose their best power control strategy in order to selfishly maximize their energy-efficiency. To increase the utilities with respect to the classical non-cooperative game, we introduce hierarchy in two ways. On the one hand, assuming singleuser decoding at the receiver, we investigate a Stackelberg formulation of the game where one user is the leader. On the other hand, assuming neither leader nor followers among the users, we introduce hierarchy by using successive interference cancelation at the receiver. For both cases, we study the existence and uniqueness of an equilibrium and compare the individual performance obtained in the hierarchical game with that obtained in the non-cooperative game. An exhaustive comparative analysis of the two games is also conducted. In order to optimize the choice of the leader in the Stackelberg formulation (with single user decoding) and that of the decoding order (in the non-cooperative game with successive interference cancelation), we study two measures of global energy-efficiency for the network and discussions are provided for each case