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An Efficient Maximum Likelihood Carrier Frequency Offset Estimator for OFDM Using Null Subcarriers and Cyclic Prefix

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Abstract

Accurate estimation of carrier frequency offset (CFO) is an important requirement in orthogonal frequency-division multiplexing (OFDM) based wireless communication systems. In this paper, we propose a hybrid procedure to accomplish this task efficiently. One of the key importance of the approach is the judicious combination of two independent estimators so as to reduce the bandwidth overhead and computational complexity over many conventional methods. It employs the cyclic prefix and a few null subcarriers, respectively, for the fractional and integer frequency offset estimations. We also propose a novel null subcarrier allocation scheme based on Fibonacci series. The range of frequency offset that can be estimated by the proposed technique is equal to the full OFDM bandwidth. Furthermore, performance of the proposed CFO estimator is mathematically analyzed by deriving an expression for the bit error probability of the receiver under Rayleigh fading channel and the Cramer-Rao lower bound for the mean square estimation error. For moderate SNRs, our approach is shown to greatly outperform some recently published methods in terms of BER performance, bandwidth overhead and receiver complexity.

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References

  1. Bölcskei H. (2001) Blind estimation of symbol timing and carrier frequency offset in wireless OFDM systems. IEEE Transactions on Communications 49(6): 988–999

    Article  MATH  Google Scholar 

  2. Chen B. (2002) Maximum likelihood estimation of OFDM carrier frequency offset. IEEE Signal Processing Letters 9(4): 123–126

    Article  Google Scholar 

  3. Chin W., Chen S. (2009) A blind synchronizer for OFDM systems based on SINR maximization in multipath fading channels. IEEE Transactions on Vehicular Technology 58(2): 625–635

    Article  Google Scholar 

  4. Daffara, F., & Adami, O. (1995). A new frequency detector for orthogonal multicarrier transmission techniques. In Proceedings of IEEE 45th Vehicular Technology Conference (pp. 804–809).

  5. Doufexi A., Armour S., Butler M., Nix A., Bull D., McGeehan J., Karlsson P. (2002) A comparison of the HIPERLAN/2 and IEEE 802.11a wireless LAN standards. IEEE Communications Magazine 40(5): 172–180

    Article  Google Scholar 

  6. Fusco T., Marrone F., Tanda M. (2008) Semiblind techniques for carrier frequency offset estimation in OFDM systems. Signal Processing 88(30): 704–718

    Article  MATH  Google Scholar 

  7. Ghogho, M., Swami, A., & Giannakis, G. B. (2001). Optimized null-subcarrier selection for CFO estimation in OFDM over frequency selective fading channels. In Proceedings of Globecom (pp. 202–206). San Antonio, TX.

  8. Huang D., Letaief K. B. (2006) Carrier frequency offset estimation for OFDM systems using null subcarriers. IEEE Transactions on Communications 54(5): 813–822

    Article  Google Scholar 

  9. IEEE 802.16 Broadband wireless access working group, channel models for fixed wireless applications, [Online], Available: http://www.ieee802.org/16/tg3/contrib/802163c-01_29r4.pdf.

  10. Kay S. M. (1993) Fundamentals of statistical signal processing: Estimation theory. Prentice Hall PTR, New Jersey

    MATH  Google Scholar 

  11. Lashkarian N., Kiaei S. (2000) Class of cyclic based estimators for frequency offset estimation of OFDM systems. IEEE Transactions on Communications 48(12): 2139–2149

    Article  Google Scholar 

  12. Lin J. C. (2000) Maximum-likelihood frame timing instant and frequency offset estimation of OFDM systems. IEEE Transactions on Communications 48(12): 2139–2149

    Article  Google Scholar 

  13. Liu H., Tureli U. (1968) A high efficiency carrier estimator for OFDM communications. IEEE Communications Letters 2: 104–106

    Article  Google Scholar 

  14. Lv T., Li H., Chen J. (2005) Joint estimation of symbol timing and carrier frequency offset of OFDM signals over fast time-varying multipath channels. IEEE Transactions on Signal Processing 53(12): 4526–4635

    Article  MathSciNet  Google Scholar 

  15. Lv T., Wan Q. (2003) Blind estimation of symbol timing and carrier frequency offset in time-varying multipath channels for OFDM systems. IEICE Transactions on Communications E86-B(9): 2665–2671

    Google Scholar 

  16. Luise M., Reggiannini R. (1996) Carrier frequency acquisition and tracking for OFDM systems. IEEE Transactions on Communications 44(11): 1590–1598

    Article  Google Scholar 

  17. Ma X., Tepedelenlioglu C., Giannakis G. B., Barbarossa S. (2001) Non-data-aided carrier offset estimators for OFDM with null subcarriers: Identifiability, algorithms, and performance. IEEE Journal on Selected Areas in Communications 19(12): 2504–2511

    Article  Google Scholar 

  18. Minn H., Bhargava V. K., Letaief K. B. (2003) A robust timing and frequency synchronization for OFDM systems. IEEE Transactions on Wireless Communications 2(4): 822–839

    Article  Google Scholar 

  19. Mo R., Chew Y. H., Tjhung T. T., Ko C. C. (2008) A new blind joint timing and frequency offset estimator for OFDM systems over multipath fading channels. IEEE Transactions on Vehicular Technology 57(5): 2947–2957

    Article  Google Scholar 

  20. Moose P. H. (1994) A technique for orthogonal frequency division multiplexing frequency offset correction. IEEE Transactions on Communications 42(10): 2908–2914

    Article  Google Scholar 

  21. Morelli M., Mengali U. (1999) An improved frequency offset estimator for OFDM applications. IEEE Communications Letters 3(3): 75–77

    Article  Google Scholar 

  22. Pollet T., Van Bladel M., Moeneclaey M. (1995) BER sensitivity of OFDM systems to carrier frequency offset and Wiener phase noise. IEEE Transactions on Communications 43(2/3/4): 191–193

    Article  Google Scholar 

  23. Sathananthan K., Tellambura C. (2001) Probability of error calculation of OFDM systems with frequency offset. IEEE Transactions on Communications 49(11): 1884–1888

    Article  MATH  Google Scholar 

  24. Schmidl T. M., Cox D. C. (1997) Robust frequency and timing synchronization for OFDM. IEEE Transactions on Communications 45(12): 1613–1621

    Article  Google Scholar 

  25. Simon M. K., Alouini M.-S. (1998) A unified approach to the performance analysis of digital communication over generalized fading channels. Proceedings of the IEEE 86(9): 1860–1877

    Article  Google Scholar 

  26. Talbot S. L., Boroujeny B. F. (2008) Spectral method of blind carrier tracking for OFDM. IEEE Transactions on Signal Processing 56(7): 2706–2717

    Article  MathSciNet  Google Scholar 

  27. The IEEE 802.16 Working group on broadband wireless access standards, IEEE 802.16 published Standards and Drafts, [Online], Available: http://wirelessman.org/published.html.

  28. Van de Beek J., Sandell M., Börjesson P. O. (1997) ML estimation of time and frequency offset in OFDM systems. IEEE Transactions Signal Processing 45(7): 1800–1805

    Article  MATH  Google Scholar 

  29. Zhu J., Lee W. (2006) Carrier frequency offset estimation for OFDM systems with null subcarriers. IEEE Transactions on Vehicular Technology 55(5): 1677–1690

    Article  Google Scholar 

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Correspondence to S. M. Sameer.

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Sameer, S.M., Raja Kumar, R.V. An Efficient Maximum Likelihood Carrier Frequency Offset Estimator for OFDM Using Null Subcarriers and Cyclic Prefix. Wireless Pers Commun 58, 259–279 (2011). https://doi.org/10.1007/s11277-009-9891-0

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