Performance of Randomized Cyclic Delay Code Encoded by Convolutional Coding

We study distributed cooperative communication systems in which a single source transmits its information with the help of multiple relays to a destination. Specifically, we consider decode and forward relay networks based on orthogonal frequency division multiplexing (OFDM). Most previous work needs a priori information for antenna allocation to obtain cooperative diversity advantages. A randomized cyclic delay code does not require additional information in order to coordinate relay transmission. We applied randomized cyclic delay code to relay protocols and analyzed its performance. Simulation results show that considerable diversity gain is obtained in cooperative communication systems.