Subcarrier, Bit and Time Slot Allocation for Multicast Precoded OFDM Systems

Ali Maiga (1) , Jean-Yves Baudais (2) , Jean-François Hélard (2)

1 IETR - Institut d'Electronique et de Télécommunications de Rennes
2 IETR - Institut d'Électronique et des Technologies du numéRique

The conventional resource allocation method in multicast OFDM systems adapts the physical layer to the worst user link conditions. In this paper, we propose new subcarrier, bit and time slot allocation algorithms for multicast OFDM systems in indoor powerline communication (PLC) context. To increase the multicast bit rate, these algorithms jointly use linear precoded OFDM (LP-OFDM) modulation technique and the conventional multicast approach to exploit the channel frequency selectivity experienced by each user. The LP technique applied to OFDM systems has already proved its ability to significantly increase the system throughput in a PLC context. Here, different groups of multicast users according to their channel conditions are created and different ways of gathering users, leading to different modes, are analyzed. Simulations are run over indoor PLC channels and it is shown that the proposed modes combined with the LP-OFDM solution offer a significant bit rate gain compared to the conventional multicast approach. In addition, the interest of gathering multicast users into groups for multicast OFDM systems in PLC context is shown.

Mots clés: Multicast; resource allocation; OFDM; Linear precoding

Domaines: Réseaux et télécommunications [cs.NI]; Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Ali Maiga, Jean-Yves Baudais, Jean-François Hélard. Subcarrier, Bit and Time Slot Allocation for Multicast Precoded OFDM Systems. IEEE ICC, May 2010, Cape Town, South Africa. pp.384 - 389. ⟨hal-00487955⟩