Self-Cancellation of Sample Frequency Offset in OFDM Systems in the Presence of Carrier Frequency Offset

Date Added: Sep 2010
Format: PDF

A self-cancellation scheme is proposed to cope with the Sample Frequency Offset (SFO) problem in OFDM systems in the presence of a Carrier Frequency Offset (CFO). Making use of the symmetry between the phase shifts caused by SFO and the subcarrier index, the authors put the same constellation symbol on symmetrical subcarriers, and combines the pairs at the receiver coherently. In this way, the SFO effects are approximately cancelled with the price of cutting down the bandwidth efficiency by half. However some array gain and diversity gain are obtained from the symmetrical combining.