A New Blind SFO Estimation Algorithm for NG-DSL Systems

Abstract

Next generation digital subscriber line (NG-DSL) gains high efficiency by taking scheme of base-band orthogonal frequency-division multiplexing (OFDM) modulation with very large subcarrier number and very high modulation levels. However, it requires high sampling synchronization precisions since sampling frequency offset (SFO) will introduce inter-carrier interference (ICI) and degrade performance. To achieve a higher synchronization, we propose a new blind SFO estimation algorithm by segmenting the OFDM symbols and then estimate SFO in iterations. The new algorithm has higher precision and faster convergence speed than the traditional pilot-aided algorithms under the condition of large subcarrier number and high modulation levels.