Synchronization Issues in OFDM Systems

Abstract

Orthogonal frequency division multiplexing (OFDM) is a bandwidth efficient modulation technique suitable for broadband wireless communications in frequency selective fading channels, yet, its performance is sensitive to timing and carrier synchronization errors. This paper provides an overview on the causes and the effects of these synchronization errors. The authors survey various symbol timing and carrier acquisition schemes available in the literature including coarse and fine synchronization techniques, using cyclic prefix or training symbols. Blind estimators, which also do not require training symbols, are discussed as viable alternatives when data throughput is very critical