Power Allocation Based on SEP Minimization in Two-Hop Decode-and-Forward Relay Networks

—The problem of optimal power allocation among the relays in a two-hop decode-and-forward cooperative relay network with independent Rayleigh fading channels is considered. It is assumed that only the relays that decode the source message correctly contribute in data transmission. Moreover, only the knowledge of statistical channel state information is available. A new simple closed-form expression for the average symbol error probability is derived. Based on this expression, a new power allocation method that minimizes the average symbol error probability and takes into account the constraints on the total average power of all the relay nodes and maximum instant power of each relay node is developed. The corresponding optimization problem is shown to be a convex problem that can be solved using interior-point methods. However, an approximate closed-form solution is obtained and shown to be practically more appealing due to significant complexity reduction. The accuracy of the appro...

• Type: Journal
• Year: 2011
• Where: CORR
• Authors: Arash Khabbazibasmenj, Sergiy A. Vorobyov
• Keywords: Average Symbol Error, CORR 2011, Education, Optimal Power Allocation, Power Allocation