摘要：

超奈奎斯特(FTN)传输具有较高的信息传输速率和频谱效率,在5G移动通信系统中具有广阔的应用前景。但是,符号间隔的压缩导致了较为严重的码间串扰,降低了载波同步的性能。针对上述问题,通过二次多项式对周期图主瓣进行拟合,得到频谱峰值的索引值,进而计算得到频率估计值,提出一种FTN信号载波同步算法,并通过增加FFT点数、将拟合法与插值算法相结合的方法对该算法进行改进。仿真结果表明,与Candan算法、邻位符号相除算法等相比,该改进算法能更好地适应FTN信号的传输特性,载波参数估计性能逼近克拉美罗界。

关键词: 载波同步, 超奈奎斯特传输, 离散傅里叶变换, 二次多项式拟合, 码间串扰

Abstract:

Faster-than-Nyquist(FTN) signaling,which is promising in 5G mobile communication,has higher information rate and spectrum efficiency.However,symbol interval’s compression resulted in infinite Inter-Symbol Interferences (ISI),which would deteriorate the performance of carrier synchronization.To solve the problem,the new carrier synchronization algorithm is proposed.The frequency can be obtained by the spectrum peak index,which can be obtained by the quadratic polynomial fitting for periodgram main lobe.In addition,the algorithm is improved by increasing the length of FFT,combining the interpolation and fitting algorithm.Simulation results indicate that improved algorithm can adapt to the FTN signaling character better than Candan’s algorithm and the adjacent symbol phase division algorithm.And the estimation performance can approach to Cramer-Rao Bound (CRB) better.

Key words: carrier synchronization, Faster-than-Nyquist(FTN) transmission, Discrete Fourier Transform(DFT), quadratic polynomial fitting, Inter-Symbol Interferences(ISI)

中图分类号: 

• TN911.7