Energy efficient relay selection for cooperative relaying in wireless multimedia networks

In existing wireless networks, supporting multimedia services is becoming more popular and important. In general, wireless multimedia networks should require energy efficiency and reliable transmission while keeping satisfactory quality of services. In this respect, cooperative communications have been considered as an efficient approach to address these demands by offering significant diversity gains over single antenna systems without increasing requirements on radio resources. In this paper, we propose a power-allocation method to optimize the decodeand- forward (DF) cooperative transmission for source and relay nodes as a means to reduce the total power consumption, while maintaining the required quality of services, and investigate fundamental characteristics of cooperative transmission in terms of power efficiency. Moreover, for a network with multiple cooperative nodes, we also propose energy efficient relay-selection rule to offer fairness at each node and implement it into a practical routing protocol. Our performance analysis is supplemented by simulation results to illustrate the significant energy savings of the proposed methods