Preamble and Pilot Design with Computationally Efficient Synchronization and Cell Search Algorithms in Cellular OFDM Systems

A computationally efficient initial synchronization technique is introduced in cellular orthogonal frequency division multiplexing downlink systems, which includes symbol timing estimation, frequency offset estimation, frame synchronization, and cell search. Novel preamble and pilot structures are proposed and a simple three-step synchronization scheme is developed based on a variety of practical conditions such as low computational complexity, time-varying frequency selective fading, limited preamble length, low peak-to-average-power ratio, and noncoherent synchronization with no channel estimation. The proposed three-step synchronization is sequentially described as (1) joint timing and frequency synchronization, (2) frame synchronization and preamble pattern identification (ID), and (3) pilot group ID. Simulation results show that the proposed technique nicely works even at low signal-to-interference-and-noise ratio regions.

[1]  Marc Moeneclaey,et al.  BER sensitivity of OFDM systems to carrier frequency offset and Wiener phase noise , 1995, IEEE Trans. Commun..

[2]  Jia-Chin Lin,et al.  Maximum-likelihood frame timing instant and frequency offset estimation for OFDM communication over a fast Rayleigh-fading channel , 2003, IEEE Trans. Veh. Technol..

[3]  Yong Soo Cho,et al.  A Synchronization and Cell Searching Technique Using Pilot Tones for OFDM Cellular Systems , 2006, IEICE Trans. Commun..

[4]  Mamoru Sawahashi,et al.  Three-step fast cell search algorithm utilizing common pilot channel for OFCDM broadband packet wireless access , 2002, Proceedings IEEE 56th Vehicular Technology Conference.

[5]  Yong Soo Cho,et al.  A preamble-based cell searching technique for OFDM cellular systems , 2003, 2003 IEEE 58th Vehicular Technology Conference. VTC 2003-Fall (IEEE Cat. No.03CH37484).

[6]  Donald C. Cox,et al.  Robust frequency and timing synchronization for OFDM , 1997, IEEE Trans. Commun..

[7]  W. C. Jakes,et al.  Microwave Mobile Communications , 1974 .

[8]  Per Ola Börjesson,et al.  ML estimation of time and frequency offset in OFDM systems , 1997, IEEE Trans. Signal Process..

[9]  Khaled Ben Letaief,et al.  A robust timing and frequency synchronization for OFDM systems , 2003, IEEE Trans. Wirel. Commun..

[10]  Steven Kay,et al.  Fundamentals Of Statistical Signal Processing , 2001 .

[11]  Y.-P. Eric Wang,et al.  Cell search in W-CDMA , 2000, IEEE Journal on Selected Areas in Communications.

[12]  Yong Hoon Lee,et al.  Use of periodic pilot tones for identifying base stations of FH-OFDMA systems , 2006, IEEE Communications Letters.