Analysis of cyclic-prefix correlation statistics and their use in OFDM timing and frequency synchronization

Abstract

OFDM systems generally utilize a periodic extension, or cyclic prefix, to aid in equalization at the receiver. The cyclic prefix also incorporates a special autocorrelation structure into the signal that can be used for timing, carrier recovery, and delay-spread estimation. Central to these techniques is estimating the N-lag correlation function at the receiver, and in this paper, we analyze this function and its estimation error and discuss the resulting performance effects. Often over-looked is the dispersive nature of the channel, as many techniques are derived under a non-dispersive model out of convenience. The dispersive channel also results in correlated estimation error, which can si..