Distributed transmission schemes for wireless communication networks

摘要: In this thesis new techniques are presented to achieve performance enhancement in wireless cooperative networks. particular, improve transmission rate and maximise end-to-end signal-to-noise ratio described. An offset scheme with full interference cancellation for a network frequency flat links four relays is introduced. This method can asymptotically, as the size of symbol block increases, maximum together diversity provided destination node has multiple antennas. A novel inter-relay that also achieves asymptotically then designed which only requires single antenna. Two- four-relay selection schemes amplify forward type networks studied order overcome degradation bit error single-relay when there feedback errors relay links. Outage probability analysis without undertaken. Outage distributed best single- two-relay networks. The advantage multi-relay no occurs adjacent cell present at nodes shown theoretically. Simulation results outage included support theoretical expressions. Finally, cognitive cooperation between certain secondary users, chosen by single-, two- presented. The assumed exploit an underlay approach, adherence constraint on primary user. performed either max−min strategy or one based maximising exact ratio. analyses again confirmed numerical evaluations.