一种新的PCC-OFDM定时时偏盲估计

A New Blind Estimation of Timing Offset for PCC-OFDM

多项式相消编码PCC是一种编码技术,在PCC-OFDM调制中,它把将发送的信息调制到一组加权的子载波而不是单个子载波中去。PCC能够显著地降低OFDM对载波频偏的敏感性。本文对PCC-OFDM系统提出了一种新的定时盲估计,估计器是在接收机中的FFT之前进行的。基于PCC-OFDM的符号波形特征,构建定时时偏估计度量函数。最大化度量来估计定时时偏。本估计器不需要训练序列、导频信号或周期前缀。仿真表明,估计器在一个OFDM符号内收敛,且误差较小。

Polynomial cancellation coding (PCC) is a coding method for OFDM in which the information to be transmitted is modulated onto weighted sub-carriers in groups rather than onto individual sub-carriers. It has previously been shown that PCC substantially reduces the sensitivity of OFDM to carrier frequency offset. This paper presents a new blind estimation methods for timing offset in PCC-OFDM communication systems. The estimation is carried out in the time domain before the execution of Fast Fourier Transform(FFT). A timing metric function based on the characteristic of PCC-OFDMs waveform in time domain is constructed. The correct timing point is calculated by maximizing a timing metric. No training symbols, pilot tones or cyclic prefix extensions are required. Simulations show that this is one-symbol convergence estimator with low error.