Cooperative communication protocol exploiting space-frequency diversity

A cooperative communication protocol exploiting the space-frequency diversity is proposed to improve the efficiency and reliability of wireless communications. The method jointly uses the independent fading channels in various frequency bands as well as various relay paths to achieve better diversity and multiplexing gain than conventional protocols. Simulations demonstrate that the protocol gives a diversity gain of 3 and a multiplexing gain of 1. Thus, this protocol achieves higher efficiency and reliability than selection relaying protocols and incremental relaying protocols. When the outage probability is required to be less than 10-2, the protocol can achieve at least 3 dB Signal-to-Noise gain over conventional methods. Thus, frequency diversity greatly enhances the cooperative communications.