Opportunistic Power Control for Multi-Carrier Interference Channels

We propose a new method for opportunistic power control in multi-carrier interference channels for delay-tolerant data services. In doing so, we utilize a game theoretic framework with novel constraints, where each user tries to maximize its utility in a distributed and opportunistic manner, while satisfying the game’s constraints by adapting its transmit power to its channel. In this scheme, users transmit with more power on good sub-channels and do the opposite on bad sub-channels. In this way, in addition to the allocated power on each sub-channel, the total power of all users also depends on channel conditions. Since each user’s power level depends on power levels of other users, the game belongs to the generalized Nash equilibrium (GNE) problems, which in general, is hard to analyze. We show that the proposed game has a GNE, and derive the sufficient conditions for its uniqueness. Besides, we propose a new pricing scheme for maximizing each user’s throughput in an opportunistic manner under its total power constraint; and provide the sufficient conditions for the algorithm’s convergence and its GNE’s uniqueness. Simulations confirm that our proposed scheme yields a higher throughput for each user and/or has a significantly improved efficiency as compared to other existing opportunistic methods.