Pseudo-noise preamble based joint frame and frequency synchronization algorithm in OFDM communication systems  

作　　者：Qingfeng Jing Ming Cheng Yuping Lu Weizhi Zhong Hongwei Yao 

机构地区：[1]College of Astronautics,Nanjing University of Aeronautics and Astronautics

出　　处：《Journal of Systems Engineering and Electronics》2014年第1期1-9,共9页系统工程与电子技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(61301105;61102069);the China Postdoctoral Science Foundation Funded Project(2013M531351);the Nanjing University of Aeronautics and Astronautics Founding(NN2012022);the Open Fund of Graduate Innovated Base(Laboratory)for the Nanjing University of Aeronautics and Astronautics(KFJJ120219)

摘　　要：Frame and frequency synchronization are essential for orthogonal frequency division multiplexing （OFDM） systems. The frame offset owing to incorrect start point position of the fast Fourier transform （FFT） window, and the carrier frequency offset （CFO） due to Doppler frequency shift or the frequency mismatch between the transmitter and receiver oscil ators, can bring severe inter-symbol interference （ISI） and inter-carrier interference （ICI） for the OFDM system. Relying on the relatively good correlation charac-teristic of the pseudo-noise （PN） sequence, a joint frame offset and normalized CFO estimation algorithm based on PN preamble in time domain is developed to realize the frame and frequency synchronization in the OFDM system. By comparison, the perfor-mances of the traditional algorithm and the improved algorithm are simulated under different conditions. The results indicate that the PN preamble based algorithm both in frame offset estimation and CFO estimation is more accurate, resource-saving and robust even under poor channel condition, such as low signal-to-noise ratio （SNR） and large normalized CFO.Frame and frequency synchronization are essential for orthogonal frequency division multiplexing （OFDM） systems. The frame offset owing to incorrect start point position of the fast Fourier transform （FFT） window, and the carrier frequency offset （CFO） due to Doppler frequency shift or the frequency mismatch between the transmitter and receiver oscil ators, can bring severe inter-symbol interference （ISI） and inter-carrier interference （ICI） for the OFDM system. Relying on the relatively good correlation charac-teristic of the pseudo-noise （PN） sequence, a joint frame offset and normalized CFO estimation algorithm based on PN preamble in time domain is developed to realize the frame and frequency synchronization in the OFDM system. By comparison, the perfor-mances of the traditional algorithm and the improved algorithm are simulated under different conditions. The results indicate that the PN preamble based algorithm both in frame offset estimation and CFO estimation is more accurate, resource-saving and robust even under poor channel condition, such as low signal-to-noise ratio （SNR） and large normalized CFO.

关 键 词：orthogonal frequency division multiplexing （OFDM） frame synchronization carrier frequency offset （CFO） estimation preamble pseudo-noise sequence. 

分 类 号：TN919.3[电子电信—通信与信息系统]