Power Optimization for Parallel OFDM Relaying Networks under Hybrid Power Constraints

This paper investigates the power control problem for parallel amplify-and-forward OFDM relaying networks under hybrid power constraints across relays. Based on the concavity of the objective function, an iterative algorithm, which definitely converges to the optimal solution, is firstly proposed for the special case where the aggregate constraint could be ignored. Then, for the general case where the multiple constraints simultaneously act, the optimal solution is obtained by solving a group of similar optimization problems and the complexity is exponential with the number of relays. Comparing with that, a linear-complexity algorithm is finally provided to construct a suboptimal solution, and the numerical results show its performance is very close to that of the optimal solution.