摘要
The primary synchronization signal and the secondary synchronization signal are respectively used to fulfill the subframe and frame synchronization in the long term evolution （LTE） systems. Based on the assumption that the channel frequency response of the primary synchronization signal symbol is nearly the same as that of the secondary synchronization symbol in frequency division duplex-LTE （FDD-LTE）, a new synchronization method is proposed. The frame synchronization success probability is simulated in different wireless channel models and the Mento-Carlo method is used in the simulation. Simulation results show that if the LMMSE channel estimation is adopted, the proposed method is robust at a low signal noise ratio （SNR） scenario and works well when cartier frequency offset and fast Fourier transform （FFT） window timing offset are considered in practical applications. The frame synchronization success probability can still exceed 99% with an SNR of 0 dB when the maximum Doppler shift is very large, which means that this robust frame synchronization method can be applicable in most mobile situations. Simulation results also show that the success probability of the proposed frame synchronization method is higher than that of the method which fulfills the frame synchronization through correlating the received secondary synchronization symbol with local sequences in practical applications.
长期演进(LTE)协议中规定的主同步信号和辅同步信号分别用来完成子帧同步和帧同步.基于频分双工长期演进(FDD-LTE)无线帧中主同步信号和辅同步信号的信道频响基本相等的假设,提出了一种帧同步方法.采用蒙特卡罗方法对该同步方法在不同信道模型下的帧同步成功概率进行了仿真.仿真结果表明:当采用线性最小均方差信道估计时,该方法的性能在存在载波频偏和快速傅立叶变换(FFT)窗定时偏差的实际应用环境中仍然很好,并且在低信噪比条件下保持鲁棒.通过在不同多普勒频移条件下进行仿真和分析,发现当信噪比大于0dB时,即使在高多普勒频移环境下,该方法的帧同步成功概率仍超过99%,这意味着此帧同步方法能适用于大多数移动通信环境.通过与利用辅同步信号的正交性,采用在频域把接收到的辅同步信号和本地序列进行相关操作完成帧同步的方法对比,该方法在存在载波频偏、FFT窗定时偏差和多普勒频移的移动应用环境中的帧同步成功概率具有明显优势.
