Fast adaptive loading for OFDM based on energy consumption intensity analysis

A fast approach of adaptive loading for Orthogonal Frequency Division Multiple Access (OFDM) is proposed. The energy consumption intensity (ECI), which denotes the energy efficiency of the subchannels is introduced here. According to the analysis of ECI, the proposed algorithm allocates as much as possible bits to each subchannel constrained by the initial ECI threshold, then it picks the bit with the least ECI, and converges fast to the target bit rate or energy constraints at a given bit error rate(BER). Here for each step the computation complexity is very low, so it works fast. Computer simulations show that the energy efficiency performance is similar to the suboptimum ones, and at the same time quiet a lot of time can be saved.