基于符号峰态的OFDM信号参数盲估计方法

Blind Estimation Method for OFDM Parameter Based on Symbol Kurtosis

针对传统的OFDM信号参数估计方法在短循环前缀条件下存在估计准确率不高、所需OFDM符号数过多等问题,提出了一种基于符号峰态的OFDM信号参数盲估计方法。首先利用OFDM信号相关参数样本区间内的预估值对接收信号进行解调,然后根据解调出的OFDM基带符号构造符号峰态特征函数,最后从理论上证明了可通过检测符号峰态的最小值实现OFDM信号循环前缀长度和有效符号长度的联合估计。实验仿真结果表明,该算法克服了传统方法难以估计短循环前缀OFDM信号参数的缺陷,仅用较少的OFDM符号数就可以实现短循环前缀OFDM信号的参数估计,并且其估计性能优于传统方法。

Aiming at the poor performance and the large required OFDM symbol number of conventional estimation method for the parameter of OFDM signal when the cyclic-prefix length is short.A method based on symbol kurtosis was proposed to estimate the parameter of OFDM signal.Firstly,we used the trial values of related parameter of OFDM signal in the sample spacing to demodulate the received signal.Secondly,we constructed the symbol kurtosis according to the demodulated baseband symbol.Finally,we proved that the joint estimation for cyclic-prefix length and useful symbol length can be achieved by detecting the lowest value of symbol kurtosis.The experimental simulation results show that the proposed method overcomes the shortcoming of conventional estimation method that it is difficult to estimate the parameter of OFDM signal when the cyclic prefix length is short,and the parameter of OFDM signal could be accurately estimated using less symbols than conventional estimation method.