Skip to main content
Log in

Optimal pilots design for frequency offsets and channel estimation in OFDM modulated single frequency networks

  • Research Paper
  • Special Focus on Convergence Communications
  • Published:
Science China Information Sciences Aims and scope Submit manuscript

Abstract

Optimal pilot design and placement for both the frequency offsets and channel estimation in Orthogonal Frequency-Division Multiplexing modulated Single Frequency Network are treated. Unlike the conventional frequency-domain filter-based algorithms, the proposed pilot of each transmitter can always be demodulated at the receiver even if the received pilots of multiple transmitters are totally overlapped. Although the channel state information is needed in designing the proposed pilot for carrier frequency offset (CFO) estimation, the performance of the proposed CFO estimation is robust to the channel estimation error. The optimal pilot as well as the Least-Squares (LS) channel estimator is also proposed, and the pilot for channel estimation is always a constant-modulus. A joint frequency offset and channel estimation scheme is also proposed, and the transmitters can adaptively optimize their pilots in the successive transmissions using the estimation results feedback in the former transmission. Simulation results demonstrate the performance of the proposed algorithm in terms of frequency offset and channel estimation accuracies. Since multiple copies of the same information can be received at each receiver, some combining technologies such as equal gain combining (EGC) or maximal ratio combining (MRC) can be applied at the receiver to improve the receiving diversity gain. Numerical results show that in a scenario of two transmitters with a Signal-to-Noise Ratio of 20 dB, the Bit Error Rate (BER) of 1.5 × 10−4 (or 1 × 10−4) can be obtained at the receiver using EGC (or MRC), and this BER performance can be improved to be 4 × 10−6 for EGC (or 2 × 10−6 for MRC) by considering three co-receiver transmitters.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Zhang Z S, Long K P, Wang J P, et al. On swarm intelligence inspired self-organized networking: its bionic mechanisms, designing principles and optimization approaches. IEEE Commun Surv Tut, 2013, 99: 1–25

    Google Scholar 

  2. Zhang Z S, Long K P, Wang J P. Self-organization paradigms and optimization approaches for cognitive radio technologies: a survey. IEEE Wirel Commun, 2013, 20: 36–42

    Article  Google Scholar 

  3. Zhang Z S, Huangfu W, Long K P, et al. On the designing principles and optimization approaches of bio-inspired self-organized network: a survey. Sci China Inf Sci, 2013, 56: 071301

    MathSciNet  Google Scholar 

  4. Shu F, Berber S, Wang D M, et al. Ml integer frequency offset estimation for ofdm systems with null subcarriers: estimation range and pilot design. Sci China Inf Sci, 2010, 53: 2567–2575

    Article  Google Scholar 

  5. Zhang Z S, Zhao M, Zhou H Y, et al. Frequency offset estimation with fast acquisition in OFDM system. IEEE Commun Lett, 2004, 8: 171–173

    Article  Google Scholar 

  6. Zhang Z S, Jiang W Y, Zhou H Y, et al. High accuracy frequency offset correction with adjustable acquisition range in OFDM systems. IEEE Trans Wirel Commun, 2005, 4: 228–237

    Article  Google Scholar 

  7. Kung T L, Parhi K K. Optimized joint timing synchronization and channel estimation for ofdm systems. IEEE Wirel Commun Lett, 2012, 1: 149–152

    Article  Google Scholar 

  8. Beek J J, Borjesson P O, Boucheret M L, et al. A time and frequency synchronization scheme for multiuser OFDM. IEEE J Select Areas Commun, 1999, 17: 1900–1914

    Article  Google Scholar 

  9. Moose P H. A technique for orthogonal frequency division multiplexing frequency offset correction. IEEE Trans Commun, 1994, 42: 2908–2914

    Article  Google Scholar 

  10. Zeng Y, Leyman A R. Pilot-based simplified ML and fast algorithm for frequency offset estimation in OFDMA uplink. IEEE Trans Veh Technol, 2008, 57: 1723–1732

    Article  Google Scholar 

  11. Barhumi I, Leus G, Moonen M. Optimal training design for MIMO OFDM systems in mobile wireless channels. IEEE Trans Signal Process, 2003, 51: 1615–1624

    Article  Google Scholar 

  12. Zhang Z, Zhang W, Tellambura C. MIMO-OFDM channel estimation in the presence of frequency offsets. IEEE Trans Wirel Commun, 2008, 7: 2329–2339

    Article  Google Scholar 

  13. Minn H, Al-Dhahir N, Li Y. Optimal training signals for MIMO OFDM channel estimation in the presnece of frequency offset and phase noise. IEEE Trans Commun, 2006, 54: 1081–1096

    Article  Google Scholar 

  14. Chen J C, Wen C K, Ting P. An efficient pilot design scheme for sparse channel estimation in OFDM systems. IEEE Commun Lett, 2013, 17: 1352–1355

    Article  Google Scholar 

  15. Zhang Z S, Zhang W, Tellambura C. Robust OFDMA uplink synchronization by exploiting the variance of carrier frequency offsets. IEEE Trans Veh Technol, 2008, 57: 3028–3039

    Article  Google Scholar 

  16. Zhang Z S, Zhang Lu, You M L, et al. Bit Error rate approximation of MIMO-OFDM systems with carrier frequency offset and channel estimation errors. EURASIP J Wirel Commun Netw, 2010, 2010: 176083

    Article  Google Scholar 

  17. Rugini L, Banelli P. BER of OFDM systems impaired by carrier frequency offset in multipath fading channels. IEEE Trans Wirel Commun, 2005, 4: 2279–2288

    Article  Google Scholar 

  18. Zhang Z S, Tellambura C. The effect of imperfect carrier frequency offset estimation on OFDMA uplink transmission. In: Proceedings of IEEE International Conference on Communications, Glasgow, 2007. 6281–6286

    Google Scholar 

  19. Cho K, Yoon D. On the general BER expression of one- and two-dimensional amplitude modulations. IEEE Trans Commun, 2002, 50: 1074–1080

    Article  Google Scholar 

  20. Yang L L, Hanzo L. A recursive algorithm for the error probability evaluation of M-QAM. IEEE Commun Lett, 2000, 4: 304–306

    Article  Google Scholar 

  21. Zhou S L, Giannakis G B, Scaglione A. Long codes for generalized FH-OFDMA through unknown multipath channels. IEEE Trans Commun, 2001, 49: 721–733

    Article  MATH  Google Scholar 

  22. Fu X, Minn H, Cantrell C D. Two novel iterative joint frequency-offset and channel estimation methods for OFDMA uplink. IEEE Trans Commun, 2008, 56: 474–484

    Article  Google Scholar 

  23. Lee J H, Kim S C. Time and frequency synchronization for OFDMA uplink system using the SAGE algorithm. IEEE Trans Wirel Commun, 2007, 6: 1176–1181

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to ZhongShan Zhang.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Li, Y., Xu, X., Zhang, D. et al. Optimal pilots design for frequency offsets and channel estimation in OFDM modulated single frequency networks. Sci. China Inf. Sci. 57, 1–12 (2014). https://doi.org/10.1007/s11432-014-5062-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11432-014-5062-3

Keywords

Navigation