Windowed OFDM versus OFDM/OQAM: A Transmission Capacity Comparison in the HomePlug AV Context
Abstract
With the HPAV specification, windowed OFDM is now the most commonly used modulation technique in PLC networks. However, another modulation, named OFDM/OQAM, could notably improve the capacity of these networks. Imposing an orthogonality condition only in the real field, this modulation offers a great flexibility in the design of the prototype filter that shapes its symbols. Nevertheless, to take advantage of this degree of freedom, a study needs to be conducted to decide which prototype filter is the most adapted for PLC networks. The prototype filter length, its time and frequency localization and its orthogonality or nearly-orthogonality properties, represent some parameters that will determine the performance of OFDM/OQAM in a particular context. So, this contribution shows the achieved throughputs by OFDM/OQAM in an in-home PLC context, using different prototype filters and following the HPAV specification mask. These throughputs are also compared to the ones provided by the windowed OFDM modulation.