FRFT-OFDM系统中FRFT域变换角度的估计  

Estimation of the Angle Parameter in FRFT Domain for FRFT-OFDM Systems

作　　者：李锋[1] 朱世华[1] 荣玫[1] 

机构地区：[1]西安交通大学信息与通信工程系,西安710049

出　　处：《电子与信息学报》2008年第10期2427-2430,共4页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60372055);博士点基金(20030698027)资助课题

摘　　要：针对FRFT—OFDM（分数阶傅里叶域的正交多载波）系统，该文提出了一种基于信道时变传输函数的FRFT域角度参数的估计算法。该算法利用信道的时变传输函数，对信道的G-特征函数中时变频率和时间的关系进行了线性近似，理论分析和仿真都表明，相对于已有的角度参数估计方法，该方法具有较低的复杂度，在子载波个数为128的系统中，该方法比传统方法复杂度可降低10^4数量级。该方法适用于信道时变性较强、多普勒频偏较大的场合。A new method of calculating the angle parameter in FRFT domain based on the eigenfunction of time-varying channel is proposed in this letter for FRFT-OFDM systems. The new scheme can estimate the angle parameter in real time based on the variation of the wireless channel. The relationship between the time-variant frequency of G-eigenfunction and time is approximated by linear function. Both theoretical analysis and computer simulation demonstrate that the new scheme has a low complexity compared with the traditional method. When the number of subcarriers is 128, the new scheme can reduce the complexity by 10^4 compared with the traditional method. This new scheme has advantage when the Doppler spread is large or the time variation of the channel is fast.

关 键 词：分数阶傅里叶变换 正交频分复用 FRFT—OFDM G-特征函数 

分 类 号：TN92[电子电信—通信与信息系统]