Increasing demand for high-speed wireless networks has motivated the development of wireless ad-hoc networks. In order to fully exploit the technological development in radio hardware and integrated circuits, which allow for implementation of more complicated communication schemes, the fundamental performance limits of wireless networks should be reevaluated. In this context, the distinct characteristics of wireless networks compared to their wired counterpart lead to more sophisticated design of protocols and algorithms. Some of the most important inherent properties of the Physical Layer (PHY) that make the design more complicated include the attenuation of radio signals over long range communications called path loss, and the fading effect caused by multipath propagation. In order to mitigate these effects, the user has to increase its transmission power or use more sophisticated reception algorithms. Another important limitation of wireless performance caused mainly as a result of communication over a limited bandwidth is the interference from other users, communicating over the same frequency spectrum. Wireless ad hoc networks are multi-hop structures, which consist of communications among wireless nodes without infrastructure. They usually have unplanned network topologies. Wireless ad hoc networks have various civilian and military applications which have drawn considerable attentions in recent years. One of the major concerns in designing wireless ad hoc networks is to reduce the energy consumption as the wireless nodes are often powered by batteries only. Wireless nodes need to save their power as well as sustain links with other nodes, since they are battery powered. Topology control deals with determining the transmission power of each node so as to maintain network connectivity and consume the minimum transmission power. Using topology control, each node is able to maintain its connection with multiple nodes by one hop or multi-hop, even though it does not use its maximum transmission power. Consequently, topology control helps power saving and decreases interferences between wireless links by reducing the number of links. Topology control is one of the key energy saving techniques which have been widely studied and applied in wireless ad hoc networks. Topology control lets each wireless node to select certain subset of neighbors or adjust its transmission power in order to conserve energy meanwhile maintain network connectivity. Topology control have been widely studied and applied in wireless ad hoc networks as one of the key energy saving techniques. In order to save energy and extend lifetime of networks topology control lets each wireless node to select certain subset of neighbors or adjust its transmission power meanwhile maintain network connectivity. Recently, a new class of communication techniques, cooperative communication (CC), has been introduced to allow single antenna devices to take the advantage of the multiple-input-multiple-output (MIMO) systems. This cooperative communication explores the broadcast nature of the wireless medium and allows nodes that have received the transmitted signal to cooperatively help relaying data for other nodes.
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