Channel uncertainty for AF wireless distributed relay networks under power constraint

This paper presents optimum relay amplifying matrices (or vectors) using the minimum mean square error (MMSE), maximum signal-to-noise ratio (SNR), zero-forcing (ZF), and matched-filter (MF) criteria for an amplify-and-forward (AF) wireless distributed relay network with a one-source-one-destination pair and iV-relay under the global power constraint (GPC) at the relays in a channel uncertainty (CU) environment. In addition, the local power constraint (LPC) at the relays is also considered for the MMSE criterion. With the derived optimum amplifying relay matrices, cost function and SNR behaviors, achievable rate, and relay selection scheme in the CU environment will be investigated theoretically and evaluated numerically.