MIMO techniques for the transmission and resource allocation in in-home Power Line Communication

Since the beginning of the 20th century, many efforts from academic institutions as well as manufacturers have been done to make power lines a transmission medium in in-home networks. Information data exchanges are expected to grow exponentially in the next decade and PLC technology should be complement to wireless technologies to manage the demand. To that purpose, the PLC technology has still to progress on two key aspects: data-rate increase and robustness. One challenging task for the purpose of high data-rates is to optimize the resource allocation (e.g. rate maximization, consumed power minimization) in PLC systems. We have addressed this problem with and without self-interference and proposed algorithms to solve it. In both cases, we have theoretically proved that the proposed solutions can yield the global optimum or at least a local optimum that is close to the global optimum. Moreover, in view of practical implementations, we have demonstrated that our algorithms are simple and low-complexity as compared to other solutions existing in the literature. Finally, the joint problem between bit allocation and guard interval adaptation has been also investigated and efficiently solved by a low-complexity and practical approach. Another task is to optimize the MIMO technique adaptation, among which the MIMO precoding. The maximum number of transmitter ports available in PLC systems is only two. In the literature, the singular value decomposition (SVD) is usually proposed to create independent streams and then transmit data on these streams. The orthogonal spatial multiplexing (OSM) is another well-known scheme of the state-of-art which outperforms the SVD scheme in terms of error rate for OFDM-based systems. We have compared both schemes for purpose of a practical implementation in MIMO-PLC systems.