共轭对称结构训练符号的多普勒频移估计算法分析

Analysis of the Doppler Frequency Shift Estimation Algorithm Based on Conjugated-symmetrical-structured Training Sequence

对利用共轭对称结构训练符号进行多普勒频移瞬时值估计的算法性能进行了分析。研究结果表明,在多普勒信道下,该算法具有较高的定时同步精度,并且可以将多普勒频移瞬时值和收、发两端的载波振荡器频偏作为一个整体进行估计,得到准确的估计结果,再进行频偏补偿,从而提高OFDM系统的性能。但在多径-多普勒信道下,该算法的定时估计精度与频偏估计精度较低,很难估计出多普勒频移瞬时值。

The instantaneous value of the Doppler frequency shift estimation Based on Conjugated-symmetrical-structured Training Sequence has been studied.The research results show that in the Doppler channel,the two algorithms have a high level of timing synchronization accuracy,and can get accurate estimation results by estimating the instantaneous value of the Doppler frequency shift and the carrier oscillator frequency offset as a whole one,and then make up the frequency offset,and finally improve the performance of the OFDM system.But in the multipath and Doppler channel,the two algorithms＇ estimation accuracy of the timing and frequency offset are so low that it will be hard to estimate the instantaneous value of the Doppler frequency shift.