Sum-Rate Maximization of Multi-User OFDMA Two-way Relay Networks under Sub-Carrier Pairing and Fairness Constraints

In this paper, we invoke sub-carrier pairing based sum-rate maximization problem in wireless cooperative networks. Two-way relaying (TWR) with amplify-and-forward (AF) protocol is considered in multi-user, multi-carrier environment over two-hop with single fixed relay station (FRS), in which direct link between source and destination is not available. We formulate to maximize the overall sumrate and individual sum-rate achieved by users subject to sub-carrier pairing and data rate fairness. The joint optimization of resources turn the problem to be combinatorial having NP-hard solution due to its utmost computational complexity. Firstly, we propose an optimal solution and then a lowcomplexity resource allocation scheme based on “Hungarian Algorithm” is presented. Finally, the simulation results of performance evaluation describe the effectiveness of sub-carrier pairing for sumrate maximization.

[1]  Wenbo Wang,et al.  Subcarrier pairing for amplify-and-forward and decode-and-forward OFDM relay links , 2009, IEEE Communications Letters.

[2]  Armin Wittneben,et al.  Spectral efficient protocols for half-duplex fading relay channels , 2007, IEEE Journal on Selected Areas in Communications.

[3]  Aria Nosratinia,et al.  Cooperative communication in wireless networks , 2004, IEEE Communications Magazine.

[4]  Elza Erkip,et al.  User cooperation diversity. Part I. System description , 2003, IEEE Trans. Commun..

[5]  Abbas El Gamal,et al.  Capacity theorems for the relay channel , 1979, IEEE Trans. Inf. Theory.

[6]  H. Kuhn.  The Hungarian method for the assignment problem , 1955 .

[7]  Il-Min Kim,et al.  Relay Selection with ANC and TDBC Protocols in Bidirectional Relay Networks , 2010, IEEE Transactions on Communications.

[8]  Elza Erkip,et al.  User cooperation diversity. Part II. Implementation aspects and performance analysis , 2003, IEEE Trans. Commun..

[9]  Feifei Gao,et al.  A Joint Resource Allocation Scheme for Multiuser Two-Way Relay Networks , 2011, IEEE Transactions on Communications.

[10]  Daniel Benevides da Costa,et al.  Outage Analysis for Multiuser Two-Way Relaying in Mixed Rayleigh and Rician Fading , 2011, IEEE Communications Letters.

[11]  Ying-Chang Liang,et al.  Two-Way Relaying over OFDM: Optimized Tone Permutation and Power Allocation , 2008, 2008 IEEE International Conference on Communications.

[12]  Yifei Yuan,et al.  IMT-advanced relay standards [WiMAX/LTE Update] , 2010, IEEE Communications Magazine.

[13]  E. Meulen,et al.  Three-terminal communication channels , 1971, Advances in Applied Probability.

[14]  Xiang Gui,et al.  Radio Resource Allocation in Multi-User Cooperative Relaying Networks with Resource Block Pairing and Fairness Constraints , 2013, Int. J. Wirel. Inf. Networks.

[15]  Ian F. Akyildiz,et al.  Mobile relay and group mobility for 4G WiMAX networks , 2011, 2011 IEEE Wireless Communications and Networking Conference.