Open Access Open Access  Restricted Access Subscription or Fee Access

Joint Symbol Timing Estimation and Carrier Phase Synchronization for OFDM based WLAN Systems

C. Geetha Priya, Dr. M. Suganthi

Abstract


In this paper, a joint symbol timing estimation and carrier phase synchronization method for Orthogonal Frequency Division Multiplexing (OFDM) system is implemented for a Wireless Local Area Network (WLAN). Earlier approaches for symbol timing estimation make use of correlation of samples within the preamble. So preamble should be chosen with good autocorrelation property. Thus estimation method directly depends on the preamble. The implemented method for timing estimation in this paper is preamble independent. This method can be applied for any preamble structure and this scheme gives more accurate estimate of symbol timing. Also a method for carrier phase recovery is implemented in OFDM WLAN system. This algorithm for carrier phase compensation can effectively recover Residual Frequency Offset (RFO) and phase in the presence of Inter Carrier Interference (ICI). This scheme for symbol timing and carrier phase recovery is analyzed for WLAN environment and simulation results are shown


Keywords


Carrier Frequency Offset (CFO), Correlation Sequence of Preamble (CSP), Decision-Directed (DD), Inter Carrier Interference (ICI), Orthogonal Frequency Division Multiplexing (OFDM), Quadrant Decision (QD), Residual Frequency Offset (RFO).

Full Text:

PDF

References


Paul H. Moose, “A Technique for Orthogonal Frequency Division Multiplexing Frequency Offset Correction”, IEEE Trans. Commun., vol.42, no. 10, pp. 2908-2914, Oct. 1994.

Timothy M. Schmidl and Donald C. Cox, “Robust frequency and Timing synchronization for OFDM”, IEEE Trans.Commun., vol. 45, no.12,pp.1613-1621, Dec. 1997.

Jean Armstrong, “Analysis of New and Existing Methods of Reducing Intercarrier Interference due to Carrier Frequency Offset in OFDM”,IEEE Trans. Commun., vol. 47, no. 3, pp.365-369, March 1999.

H.Minn,M.Zeng and V.K.Bhargava, “On Timing Offset estimation for OFDM systems”, IEEE Commun. Lett. vol.4, no.7, pp.242-244, July 2000.

Byungjoon Park, Hyunsoochoen, Eunseok ko, Changeon kang, et al, “A Novel timing estimation method for OFDM systems”, IEEE Commun.Lett., vol.7, no.5, pp.53-55, May 2003.

G.Ren, Y.Chang, H.Zhan and H.Zhang, “Synchronization method based on a new constant envelope preamble for OFDM systems”, IEEE Trans.Broadcast., vol. 51, no.1, pp.139-143, March 2005.

K. Shi, E.Serpedin, and P.Ciblat, “Decision-directed fine synchronization in OFDM systems”, IEEE Trans.Commun., vol.53, no.3, pp-408 - 412,March 2005.

K. Nikitopoulos and A. Polydoros, “Phase-impairment effects and compensation algorithms for OFDM systems”, IEEE Trans. Commun.,vol. 53, no. 4, pp. 698–707, April. 2005.

Ki Yun Kim, Qiyue Zou, Hyung Jin Chi, and Ali H. Sayed , “An Efficient Carrier Phase Synchronization Technique for High-Order M-QAM–OFDM”, IEEE Transactions Signal Processing, , vol. 56, no. 8,pp. 3789-3794, August 2008.

Feifei Gao, Tao Cui, A. Nallanathan, and C. Tellambura, “Maximum Likelihood Based Estimation of Frequency and Phase Offset in DCT OFDM Systems under Non-Circular Transmissions: Algorithms,Analysis and Comparisons”, IEEE Trans. Commun., vol. 56, no. 9, pp. 1425-1429 Sept. 2008.

Yeonsu Kang, Sooy oung Kim, D oseob Ahn and Hojin Lee, “Timing Estimation for OFDM Systems by using a Correlation Sequence of Preamble”, IEEE Trans. Consumer Electronics, vol.54, no.4, pp.1600-1608, Nov. 2008.


Refbacks

  • There are currently no refbacks.


Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.