Best relaying protocol selection for cooperative networks

Cooperative communication has been recently proposed in wireless communication systems for exploring the inherent spatial diversity in relay channels. In this work we investigate the performance of selecting best protocol between amplify and forward (AF) and decode and forward (DF) in multiple relay networks. In the selection scheme, the best protocol between AF and DF is selected depending on source-relay links qualities. Particularly we derive the asymptotic closed form expression for the symbol error rate (SER) for the system under studied and show that our scheme maintains full diversity order and is better than fixed protocols. Numerical results are also presented to validate the theoretical analysis.