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We study the problem of optimizing the symbol error probability (SEP) performance of cluster-based cooperative wireless sensor networks (WSNs). We propose that to achieve the minimum SEP at the destination, a joint optimization of power allocation and relay selection should be accomplished. To this aim, we reformulate the SEP performance of a simple cluster-based cooperative WSN in the general form and solve the joint optimization problem efficiently. Simulation results demonstrate that the proposed joint optimization can efficiently improve the SEP performance of the network in comparison with the previous disjoint optimal relay selection schemes  

We study the problem of optimizing the symbol error probability (SEP) performance of cluster-based cooperative wireless sensor networks (WSNs). It is shown in the literature that an efficient relay selection protocol based on simple geographical information of the nodes to execute the cooperative diversity transmission, can significantly improve the SEP performance at the destination of such networks. Also, a similar analysis on the optimal power allocation for the source and the relay exists in the literature. However, we propose that to achieve the minimum SEP at the destination, a joint optimization of power allocation and relay selection should be accomplished. To this aim, we... 

We consider the non-cooperative multiple access relay channel, where N users transmit their information to a common receiver with the assistance of a shared relay. For N = 2 independent sources and dual-frequency operation (i.e. two separate frequency channels are available for transmission), it has been recently shown [1, 2] that additional diversity gain can be attained by simply switching the transmit frequency bands between users at the relay site, thus reducing the scenario to a 2 × 2 MIMO channel with achievable diversity order equal to 2. In this paper we propose to extend this previous work to the case where the sources are spatially correlated. Under a Detect-and-Forward (DF) relay...