Performance of an Adaptive Multiuser OFDM Uplink with Carrier Frequency Offsets

Using an OFDM based uplink for the future cellular network has been a controversial issue due to difficulties in time and frequency synchronization and high Peak-to-Average Power Ratio (PAPR). In this paper, a model is provided to quantify the effects of carrier frequency offsets in a multiuser OFDM uplink. We propose a slotted OFDM radio interface, in which time-frequency bins are allocated adaptively to different users based on their channel conditions. Frequency division duplex (FDD) is assumed, which enables the feedback of synchronization and scheduling information. The theoretical evaluations show that the attainable spectral efficiency highly depends on the carrier frequency offset. The results indicate that the loss in spectral efficiency is small with no more than 2% carrier frequency offset of the subcarrier spacing.

• Type: Conference
• Year: 2006
• Where: VTC
• Authors: Wei Wang, Tony Ottosson, Tommy Svensson
• Keywords: Carrier Frequency Offset, OFDM, OFDM Based Uplink, VTC 2006