Threshold-Based Relay Selection for Cooperative Wireless Network

Cooperative communication plays a vital role in the wireless domain recently due to its numerous benefits such as coverage extension, improvement in spectral efficiency, and throughput by increasing the complexity of the system. Furthermore, security becomes a key issue for implementing a cooperative communication system. In this thesis, the complexity is reduced by employing differential modulation as they do not require complete channel state information (CSI). Different threshold-based relay selection schemes are also proposed to reduce complexity. Furthermore, the security issue in the cooperative wireless network is addressed by enhancing the physical layer security using the proposed double threshold-based optimal relay selection scheme

Performance Analysis of a Threshold-Based Relay Selection Algorithm in Wireless Networks

Relay selection is an effective method to realize the cooperative diversity gain in wireless networks. In this paper, we study a threshold-based single relay selection algorithm. A reasonable threshold value is set at each relay node, and the first relay with the instantaneous channel gain larger than the threshold will be selected to cooperate with the source. The exact and closed form expression for its outage probability is derived over independent, non-identically distributed (i.n.i.d) Rayleigh channels. The complexity of the algorithm is also analyzed in detail. Simulation results are presented to verify our theoretical analysis