Kanal durum bilgisinin kablosuz röle ağları üzerindeki etkisi

In the last decade, rising demand for high data rate transmissions over wireless channels has led the wireless research to focus on new transmission schemes supporting high data rates. As a candidate structure that allows high date rate transmissions, wireless relay networks have attracted significant interest. The network capacity values achieved by relay networks increase when the nodes have multiple antennas for transmission. Thus, combining the effects of relaying and MIMO communications, MIMO relay networks promise high performance in terms of network capacity. Higher data rates are possible with MIMO relay networks when relay selection, power allocation and beamforming strategies are utilized.Intelligent selection of relay nodes, power allocation and beamforming strategies require the knowledge of related channel conditions at the transmitting nodes. In this thesis, we propose novel transmission strategies and present the impact of channel state information availability at the transmitting nodes on the design of the proposed schemes. These schemes employ intelligent relay selection, power allocation and beamforming methods based on the available channel state information. We compare the system performances of different transmission models for amplify-and-forward and decode-and-forward MIMO relay networks using an information theoretic approach.