基于部分检测相关的OFDM符号同步新算法

Novel Symbol-Synchronization Algorithm for OFDM Based on Partial Measuring Correlation

在DVB-T(D igitalTerrestrialV ideo B roadcasting)系统中,针对传统ML(M aximum L ikelihood)符号同步算法在多径信道中估计误差大,实现复杂度高的缺点,提出一种新的OFDM(O rthogonal Frequency D ivisionMu ltip lexing)盲符号同步算法———部分检测相关(PMC:Partial M easuring Correlation)算法。该算法基于OFDM信号的自相关性,通过检测OFDM部分循环前缀(CP:Cyc lic Prefix)的自相关结果估计符号同步。相对于传统的最大似然(ML)算法,PMC算法省去了保护间隙(G I:Guard Interval)检测模块,且相关运算量降低;同时,在多径信道下估计误差远小于传统ML算法。通过理论分析和计算机仿真说明了PMC盲符号同步算法的良好性能和低复杂度。

In DVB-T （Digital Terrestrial Video Broadcasting） system, to the shortage of high estimation error in multi-path channel and high implementation complexity of conventional ML （ Maximum Likelihood ） algorithm, a novel blind symbol synchronization algorithm is proposed for OFDM （Orthogonal Frequency Division Multiplexing） system. Based on autocorrelation property of OFDM signal, the symbol start point is estimated by measuring the partial CP （ Cyclic Prefix ） correlation results. Comparing with conventional ML method, the proposed PMC （Partial Measuring Correlation） algorithm does not require the GI （Guard Interval） estimate module and reduces the operation amount as calculating the correlation results by partial CP. The estimation error of PMC algorithm is much lower than that of the conventional ML method in multi-path channel. Good performance and low complexity of the proposed PMC algorithm are shown in the analysis and the simulations.