Impact of a Carrier Frequency Offset on Unique Word OFDM

Communication systems have to cope with a variety of non-idealities. Among those, carrier frequency offset (CFO) induced impairments denote a challenging task for any system, but especially for multi-carrier schemes such as orthogonal frequency division multiplexing (OFDM). Unique Word-OFDM (UW-OFDM) is a known variant, which provides various performance benefits over conventional cyclic prefix (CP) based OFDM. In particular, UW-OFDM features excellent spectral sidelobe suppression properties and an outstanding bit error ratio performance. In this work, we expand the investigations to CFO impairments, analyze the varying effects experienced by different UW-OFDM realizations and compare it against conventional OFDM as well as single-carrier systems. Through an error analysis it is shown that compared to CP-OFDM, UW-OFDM has a significantly higher robustness against CFO. This advantage becomes even more dominant with an increasing CFO.