Dynamic Subchannel and Power Allocation in OFDMA-Based DF Cooperative Relay Networks
This paper focuses on subchannel and power allocation problem in OFDMA-based Decode-and-Forward (DF) cooperative relay networks. The objective of this problem is to maximize the total data rate under the constraints of joint total transmission power and subchannels occupation, while maintaining the maximum fairness among multiple relay nodes. The authors transform this mixed integer programming problem to a standard convex optimization one through Lagrangian relaxation method. Accordingly, the optimal solution can be achieved by using Karush-Kuhn-Tucker (KKT) conditions.