提出一种新的适用于TDS—OFDM系统的频偏估计算法,利用PN序列的时域循环特性进行预频偏调整,然后用变步长扫频进行大频偏的估计,定时同步之后再利用PN的时域循环特性进行细偏估计。给出了推导过程与仿真结果,并与各种算法进行了比较。结果表明,在高斯和多径信道下此算法均能快速纠正大范围的频偏。
A new frequency estimation algorithm for Time Domain Synchronization OFDM (TDS-OFDM) system is proposed, which utilizes the time domain circular characteristic of PN sequences to adjust frequency offset and then uses a variable step frequency scan scheme to estimate large frequency offset. After timing recovery, the time domain circular characteristic of PN sequences is utilized again to estimate fine frequency offset. Both derivation and simulation are given,and it is shown that this algorithm provides wide acquisition range and high acquisition speed in gauss and multi-path channels.