Multi-Carrier Division Duplex Toward Flexible Wireless Networks

In this paper, we propose a new duplex scheme based on the multi-carrier transmission technology, multi-carrier division duplex (MCDD). MCDD exploits a time-spreading technique, the aim of which is reducing an impact of inter-link interference due to loss of orthogonality. When MCDD exploits the time-spreading with one of spreading factor, we regards this one as orthogonal frequency division duplex (OFDD), which we proposed in our previous literatures. On the other hand, when MCDD exploits greater than one of spreading factor, we regards this one as multi-carrier code division duplex (MC-CDD). We investigate how time-spreading improves the performance of MCDD system in the presence of carrier frequency offset by computer simulation. From the results, we confirm that OFDD is tolerable to the inter-link interference due to the normalized carrier frequency offset of up to 0.1. We also confirm that MC-CDD with time-spreading reduces the impact of inter-link interference and improves the performance even when the normalized carrier frequency offset is 0.5.