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This work introduces a novel resource allocation technique for dealing with linear and periodically time‐varying power line channels when an orthogonal frequency division multiplexing scheme is applied. By exploiting the correlations within one cycle of the mains signal, among cycles of mains signal and a combination of these connections, the proposed technique can offer three distinct trade‐offs between computational complexity reduction and data‐rate loss. Numerical results, which are based on measured data, are used to analyse these trade‐offs, when these inter‐cycle and intra‐cycle relationship are taken into account. Also, we verify that the use of the normalised signal‐to‐noise ratio incurs very low performance degradation, and because of computational complexity rationale, its use is strongly recommended. Additionally, we show that those cases, in which the correlations among the cycles of the mains signal is relevant, offer the best trade‐off between computational complexity reduction and data‐rate loss. Finally, we show that the proposed technique can achieve the optimal data‐rate and offers substantial improvements in terms of computational complexity when compared with existing approaches, including the Institute of Electrical and Electronics Engineers 1901 standard. Copyright © 2015 John Wiley & Sons, Ltd.

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This work organizes and discusses important information on resource allocation in power line communication (PLC) systems based on the Hermitian symmetric orthogonal frequency-division multiplexing scheme. In the context of this work, the term resource refers to bits and transmission power, which can be optimally or sub-optimally allocated to subcarriers on the basis of the knowledge of the normalized signal-tonoise ratio (nSNR) of power line subchannels. In this sense, we thoroughly discuss the formulation of the resource allocation for PLC systems and accordingly derive expressions for the nSNR as well as bit and transmission power allocation in all subchannels. Additionally, we precisely detail greedy algorithms to assist practitioners and researchers in the implementation of the resource allocation procedure. Considering a frequency-selective PLC channel corrupted by additive colored Gaussian noise as well as M-ary pulse amplitude modulation and quadrature amplitude modulation as modulation schemes, the influence of the gap from the Shannon capacity curve on symbol error rate probability is discussed. On top of the carried out discussion, numerical results are presented in order to emphasize the usefulness of a proper comprehension of this subject.