ANALYSIS OF A FRAME- AND FREQUENCY SYNCHRONIZER FOR (BURSTY) OFDM

Analytical results for a frame- and car- rier frequency synchronization scheme with repetition preamble (2) are derived. When such a preamble is composed of random Orthogonal Frequency{Division Multiplexing (OFDM) symbols with cyclic preflx, a surprising statistical efiect occurs in non{dispersive channels; the lock{in probability of the frame synchro- nizer is non{uniformly distributed inside the valid syn- chronization range. This efiect is illuminated with a theory which perfectly corresponds to simulation re- sults. Furthermore, we provide an expression for the variance of the normalized frequency estimate in the presence of frame synchronization errors. This result can be used to design the required preamble length to achieve a prescribed burst frequency accuracy.

[1]  Gottfried Ungerboeck,et al.  Rapid Training of a Voiceband Data-Modem Receiver Employing an Equalizer with Fractional-T Spaced Coefficients , 1987, IEEE Trans. Commun..

[2]  Kaveh Pahlavan,et al.  Wideband local access: wireless LAN and wireless ATM , 1997 .

[3]  Gerhard Fettweis,et al.  Burst synchronization for OFDM-based cellular systems with separate signaling channel , 1998, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[4]  J.B. Huber,et al.  A comparison of peak power reduction schemes for OFDM , 1997, GLOBECOM 97. IEEE Global Telecommunications Conference. Conference Record.

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

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

[7]  Hikmet Sari,et al.  Transmission techniques for digital terrestrial TV broadcasting , 1995, IEEE Commun. Mag..

[8]  Lajos Hanzo,et al.  Orthogonal frequency division multiplex synchronisation techniques for wireless local area networks , 1996, Proceedings of PIMRC '96 - 7th International Symposium on Personal, Indoor, and Mobile Communications.

[9]  B.C. Lovell,et al.  The statistical performance of some instantaneous frequency estimators , 1992, IEEE Trans. Signal Process..

[10]  Heinrich Meyr,et al.  OFDM burst frequency synchronization by single carrier training data , 1997, IEEE Communications Letters.

[11]  Heinrich Meyr,et al.  Frame synchronization of OFDM systems in frequency selective fading channels , 1997, 1997 IEEE 47th Vehicular Technology Conference. Technology in Motion.

[12]  M. Alard,et al.  Principles of Modulation and Channel Coding for Digital Broadcasting for Mobile Receivers , 1987 .

[13]  Paul H. Moose,et al.  A technique for orthogonal frequency division multiplexing frequency offset correction , 1994, IEEE Trans. Commun..

[14]  S.H. Muller-Weinfurtner.  On the optimality of metrics for coarse frame synchronization in OFDM: a comparison , 1998, Ninth IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (Cat. No.98TH8361).