研究OFDM系统中的同步问题. 通过对LFM信号在分数阶傅里叶域能量汇聚性的分析,提出一种基于FRFT的具有较低复杂度的联合载波频率、采样频率以及符号定时的同步算法.该算法在分数阶傅里叶域对由插入到OFDM符号中的LFM信号所产生的对称点进行搜索,结合FRFT的时移、相移以及分数阶卷积等性质,对3种偏差进行估计.仿真结果表明,该算法的性能随LFM信号长度的增加而提高,且优于其他同类算法.
Synchronization for the OFDM system is studied. A synchronization algorithm with low complexity for joint carrier frequency, sampling frequency, and symbol timing is proposed based on the property of LFM convergent energy in fractional Fourier domain. The three kinds of offset are estimated by locating symmetry point caused by LFM inserted in OFDM symbol. The simulation results show that the performance of the proposed algorithm is improved when the LFM length increases and it is better than those of other similar algorithms.
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