Energy Minimization in OFDMA Downlink Systems: A Sequential Linear Assignment Algorithm for Resource Allocation

We propose a sequential linear assignment algorithm (SLAA) for resource allocation of OFDMA systems consisting of M users and N (N > M) resource blocks, with the aim of achieving near optimal energy consumption with polynomial complexity. The proposed SLAA allocates subchannels through a linear assignment algorithm (LAA), sequentially; thus, it requires O(M N-2(N - M)(2)) complexity. From numerical results, the required power from the proposed assignment is observed to be within around 0.4 % of the lower bound of minimum possible power required to achieve the same target rates.