南京大学学报（自然科学版）2016，Vol.52Issue(6)：1121-1126,6.DOI:10.13232/j.cnki.jnju.2016.06.016
高速无线通信高阶多普勒谱估计方法
Method of high order Doppler frequency shift estimation for high-speed wireless communication
摘要
Abstract
Doppler effect is the main problem caused by high-speed movement of mobile terminal,which is a major contributing factor in decline in the quality of the communication system.The bit error rate(BER)and inter-carrier interference (ICI )increases that are attributed to large Doppler frequency shift.Research on the frequency compensation has important application value.Up to now,several methods have been proposed for estimating and compensating the one-order phase,such as level crossing rate(LCR),fast Fourier transform(FFT)and so on.Given that the high-order Doppler effect is less studied at present,the paper studies the problem of low precision and poor real-time performance of current Doppler shift compensation and a better compensation method in which the previous Doppler frequency shift and the changing rate are leveraged to estimate the current Doppler frequency shift is expected.The results show that the transverse motion of high-speed movement of the receiver will make the spectrum broaden,resulting in linear frequency modulated signal effect.And it cannot be compensated by conventional method.Furthermore,the high-order Doppler estimation and its compensation method are studied.The research indicates that the high-order spectrum is mainly composed of the transverse motion and the radial acceleration motion,and high-order spectral compensation can solve the impact of the majority of motion on the com-munication system including these two kinds of motion.And the phase difference is used to estimate the transverse velocity of terminal and then the frequency shift will be calculated.After that,the one-order and two-order phase compensation can be performed.Simulation results show the effectiveness of the method,and indicate that by combining the conventional Doppler estimation and the high-order Doppler estimation proposed in this paper,the signal can be effectively restoredand the BER can be reduced,even under low signal to noise ratio(SNR).关键词
频率补偿/无线通信/误码率/多普勒频移Key words
frequency compensation/wireless communication/BER/Doppler frequency shift分类
信息技术与安全科学引用本文复制引用
贾鸣华,张兴敢..高速无线通信高阶多普勒谱估计方法[J].南京大学学报（自然科学版）,2016,52(6):1121-1126,6.基金项目
毫米波国家重点实验室开放课题(K201514) （K201514）
