Spieltheoretische Resourcenvergabe in drahtlosen interferenzgestörten Netzwerken

Final Report Abstract

Characterization and parametrization of the achievable rate regions in interference channels has been successfully made for the K-user MISO IFC with single-user decoding receivers. We provide a framework to determine the efficient beamforming vectors in a general MISO setting. In this setting, perfect CSI at the transmitters is assumed. Moreover, the performance measures must be monotonic with the power gains at the receivers. For the two-user case with perfect CSI at the transmitters, the Pareto boundary of the achievable rate region is characterized in closed-form by relating the setting to an exchange economy. With imperfect CSI at the transmitters, we characterize and parameterize all robust Pareto optimal beamforming vectors in the K-user MISO IFC. Noncooperative games are studied in a setting with two base stations operating on protected and shared bands. The conditions for the stability of the corresponding Nash equilibrium are characterized for the case of single and multiple antennas at the transmitters. In order to suppress untruthful feedback from the mobile users regarding CSI, tools from mechanism design are applied. In the two-user MISO IFC with secrecy constraint, cooperative Pareto optimal and noncooperative operation of the links are characterized. The Nash equilibrium with secrecy is studied regarding uniqueness and stability. It is shown that the noncooperative performance of the links with secrecy constraints is better than that without secrecy. Motivated by the interference constraints in cognitive radio settings, we provide the necessary nullshaping constraints on the transmissions in the MISO IFC such that the Nash equilibrium is Pareto optimal. This result brings us to develop a greedy user selection algorithm to maximize the achievable sum rate in an underlay cognitive radio setting with existing primary receivers. We develop coordination mechanisms in the MISO IFC in order to improve the performance of the links from the Nash equilibrium. By modeling the situation between two MISO links as a competitive market, the unique Walrasian equilibrium is characterized. The Walrasian equilibrium is Pareto optimal and dominates the Nash equilibrium. We propose coordination mechanisms realized by a coordinator who forwards the necessary information to the transmitters to calculate the beamforming vectors in a decentralized manner corresponding to the Walrasian equilibrium. Through direct cooperation between two MISO links, we propose a cooperative bargaining process between the links which requires four-bit signaling in each iteration. The process is proven to terminate at an operating point arbitrary close to the Pareto boundary dominating the Nash equilibrium. In the K-user MISO IFC, coalition formation games are studied in which possible cooperation strategies between the links correspond to simple non-iterative schemes as ZF or WF precoding. Theoretical results on the conditions of full cooperation and no cooperation are provided for the ZF cooperation scheme. Moreover, we apply a distributed coalition formation algorithm to determine stable link grouping. This mechanism requires direct communication between the links and the resulting stable state improves the performance of the links from the Nash equilibrium.

Publications

• Power control game in protected and shared bands: Manipulability of Nash equilibrium. In Proc. 1st International Conference on Game Theory for Networks (GameNets), pages 428–437, May. 2009
  E. A. Jorswieck and R. Mochaourab
  
• Resource allocation in protected and shared bands: Uniqueness and efficiency of Nash equilibria. In Proc. 3rd ICST/ACM International Workshop on Game Theory in Communication Networks (Gamecomm), pages 1–10, Oct. 2009
  R. Mochaourab and E. A. Jorswieck
  
• Secrecy rate region of MISO interference channel: Pareto boundary and non-cooperative games. In Proc. 13th International ITG Workshop on Smart Antennas (WSA), Feb. 2009
  E. A. Jorswieck and R. Mochaourab
  
• Bargaining and beamforming in interference channels. In Proc. 44th Asilomar Conference on Signals, Systems, and Computers (ACSSC), pages 1–5, Nov. 2010
  R. Mochaourab, E. A. Jorswieck, K. M. Z. Ho, and D. Gesbert
  
• Beamforming in underlay cognitive radio: Null-shaping constraints and greedy user selection. In Proc. 5th International Conference on Cognitive Radio Oriented Wireless Networks (CROWNCOM), pages 1–5, Jun. 2010
  E. A. Jorswieck and R. Mochaourab
  
• Beamforming in underlay cognitive radio: Null-shaping design for efficient Nash equilibrium. In Proc. 2nd International Workshop on Cognitive Information Processing (CIP), pages 476–481, Jun. 2010
  E. A. Jorswieck and R. Mochaourab
  
• Coalition formation in MISO interference channels. In Proc. IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), pages 237–240, Dec. 2011
  R. Mochaourab and E. A. Jorswieck
  
• Optimal beamforming in interference networks with perfect local channel information. IEEE Trans. Signal Process., 59(3):1128–1141, Mar. 2011
  R. Mochaourab and E. A. Jorswieck
  
• Walrasian equilibrium in two-user multiple-input single-output interference channel. In Proc. IEEE International Conference on Communications (ICC), Workshop on Game Theory and Resource Allocation for 4G, pages 1–5, Kyoto, Japan, Jun. 2011
  R. Mochaourab and E. A. Jorswieck
  
• Exchange economy in two-user multiple-input single-output interference channels. IEEE J. Sel. Topics Signal Process., 6(2):151–164, Apr. 2012
  R. Mochaourab and E. A. Jorswieck
  
• Robust beamforming in interference channels with imperfect transmitter channel information. Signal Processing, 92(10):2509–2518, Mar. 2012
  R. Mochaourab and E. A. Jorswieck