| This thesis focuses on the power allocation during the channel training process for three cooperative relay networks: a one-way single-relay network, a one-way multi-relay network and a two-way single-relay network. For these three networks, under the amplify-and-forward (AF) scheme, we investigate the power allocation problem during the channel training process for the destination or both terminals in the case of the two-way single-relay network to estimate the global channel state information (CSI) of the whole network. Linear minimum-mean-square-error (LMMSE) estimation is adopted. The mean-square-error (MSE) of the channel estimation and the outage probability (OP) of the network with channel estimation error are derived. Closed-form solutions for the power allocation problems based on MSE minimization and OP minimization are obtained. Our simulation results demonstrate that the proposed MSE-based and OP-based power allocation schemes are superior to even power allocation. |
