A Blind Maximum-SINR Synchronization Technique for OFDM Systems

Abstract

This work presents a blind synchronizer for orthogonal frequency-division multiplexing (OFDM) systems based on signal-to-interference-and-noise-ratio (SINR) maximization. Due to the incurred losses from inter-symbol interference (ISI) and inter-carrier interference (ICI) introduced by synchronization errors, the SINR of the received data drops drastically. By taking advantage of this characteristic, both the symbol time and carrier frequency offsets are intuitively estimated by maximizing the SINR metric. For the SINR metric, we propose a blind SINR estimation, which does not need prior knowledge of the channel profiles and transmitted data. As such, the proposed maximum-SINR (MSINR) synchronization algorithm is non-data-aided (NDA) so that the transmission efficiency can be improved. Moreover, to reduce the computational complexity, the early-late gate (ELG) technique is proposed for the implementation of the synchronizer. Simulation results exhibit better performance for the MSINR algorithm than conventional techniques in multipath fading channels.