A two‐level cooperative game‐based approach for joint relay selection and distributed resource allocation in MIMO‐OFDM‐based cooperative cognitive radio networks

Abstract

We consider the downlink of a multi‐input multi‐output orthogonal frequency‐division multiplexing‐based cooperative cognitive radio network in which the secondary users (SUs) with extra resources work as relay to help the SUs with less available resources to improve their utility in terms of the throughput and fairness by forming a coalition graph. We model the problem of joint relay selection and power allocation in multi‐input multi‐output orthogonal frequency‐division multiplexing‐based cooperative cognitive radio network as a two‐level cooperative game problem, and the objectives of this work are twofold. Firstly, we assign each weak SU to one of the relays (rich SUs) through solving a problem achieved by a non‐transferable utility coalition graph game, and this comprises the first level of the game. Secondly, we jointly allocate available channels to the SUs such that no subchannel is allocated to more than one SU and simultaneously optimise the transmit covariance matrices of nodes based on the Nash bargaining solution, which is the second level of the game. We further model the network as a multi‐cell scenario with small serving areas. After relaxing the problem and convexifying the relaxed version, we develop an optimal distributed algorithm, using dual decomposition. Afterwards, we propose a dynamic distributed resource allocation algorithm for this purpose. Simulations confirm the convergence of our distributed algorithms to the globally optimal solution of the two‐level game. Copyright © 2014 John Wiley & Sons, Ltd.

MIMO-OFDM Based Energy Harvesting Cooperative Communications Using Coalitional Game Algorithm

“…It is shown in [28] that in the large-SNR regime, the grand coalition is stable and always preferred, which means that users acting in coalition cannot do worse than acting alone. In [29], a twolevel game has been proposed for joint relay selection and resource allocation in MIMO-OFDM cooperative cognitive radio networks. The first level of the game of [29] is a nontransferable utility coalition graph game, while the Nash Bargaining approach is the second level.…”

“…In [29], a twolevel game has been proposed for joint relay selection and resource allocation in MIMO-OFDM cooperative cognitive radio networks. The first level of the game of [29] is a nontransferable utility coalition graph game, while the Nash Bargaining approach is the second level. In [30], a hedonic coalitional game has been proposed to maximize the capacity of a cooperative broadcast network with simultaneous wireless information and power transfer.…”

“…In the last case, some players may be unsatisfied by the payoff allocation of the core and may have the will to leave the coalition. The solution proposed in [29] is interesting from the formal viewpoint, but the proposed two-level cooperative game is computationally expensive and requires the relaxing of some constraints in order to become tractable. The hedonic game solution proposed in [30] is conceptually attractive, but also computationally prohibitive.…”

Combining super‐orthogonal space‐frequency trellis coding, constellation shaping by shell mapping, and OFDM for high data rate broadband mobile communications

“…In this section, we propose a broadband wireless transmission system in which we combine super-orthogonal spacetime trellis coding, constellation shaping by shell mapping and OFDM for better performance. Several MIMO-OFDM uncoded schemes are analysed in [23][24][25][26][27][28]. As reference, we consider a transmission system of the same data rate but using only basic OFDM.…”

“…The functions a 2 .i/ and z 2 .i/, while easy to compute using Equations (25) and (26), are given for convenience in Table II. For the same reason, we explicitly give the result of applying the said algorithm in Table III.…”