Relays selection with power allocation in relay networks

Recently, the cooperative wireless communication system is attracting attention as 4G and beyond 4G techniques. Transmit rate and diversity are generally enhanced in MIMO systems, however, mobile devices are limited by size or hardware complexity to set many multi-antennas. The cooperative communication system has been proposed that enables mobiles to share their antennas as relays and obtain a virtual multiple-antenna transmitter. In this paper, we consider a cooperative system with AF (Amplify-and-Forward) protocol having K relays and transmitting signal individually and simultaneously. The relationships between the channel capacity and the number of selected relays will be investigated and the simulation results show that the relation between both is quasi-linear.