This paper suggests a pilot-free frequency tracking scheme for ultra-wideband orthogonal frequency-division multiplexing (UWBOFDM) receivers. The proposed scheme uses a frequency-domain spreaded data symbols which is provided in the current UWB-OFDM system. Based on this property, we develop an improved frequency synchronization receiver without the use of pilot symbols. The simulation results indicate that the proposed scheme achieves much better performance than the conventional pilot-based schemes.
2. Soliman, M. S., A. Hirata, T. Morimoto, and Z. I. Kawasaki, "Numerical and experimental study on three-dimensional localization for ultra-wideband impulsive noise sources," Journal of Electromagnetic Waves and Applications, Vol. 19, No. 2, 175-187, 2005.
doi:10.1163/1569393054497276
3. Jeong, Y. S. and J. H. Lee, "Estimation of time delay using conventional beamforming-based algorithm for UWB systems," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 15, 2413-2420, 2007.
doi:10.1163/156939307783134281
4. Liu, Y. J., Y. R. Zhang, and W. Cao, "A novel approach to the refraction propagation characteristics of UWB signal waveforms," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 14, 1939-1950, 2007.
doi:10.1163/156939307783152966
5. Batra, A., MultiBand OFDM physical layer specification, MultiBand OFDM Alliance Special Interest Group, 2005.
6. Batra, A., J. Balakrishnan, G. R. Aiello, J. Foerster, and A. Dabak, "Design of a multiband OFDM system for realistic UWB channel environments," IEEE Trans. Microwave Theory and Techniques, Vol. 52, No. 9, 2123-2138, 2004.
doi:10.1109/TMTT.2004.834184
7. ECMA International, Standard ECMA-368, High rate ultra wideband PHY and MAC standard, 2005.
8. Xiao, S., J. Chen, X.-F. Liu, and B.-Z. Wang, "Spatial focusing characteristics of time reversal UWB pulse transmission with different antenna arrays," Progress In Electromagnetics Research B, Vol. 2, 223-232, 2008.
doi:10.2528/PIERB07112203
9. El-Fishawy, N., M. Shokair, and W. Saad, "Proposed MAC protocol versus IEEE802.15.3a for multimedia transmission over UWB networks," Progress In Electromagnetics Research B, Vol. 2, 189-206, 2008.
doi:10.2528/PIERB07111812
10. Naghshvarian-Jahromi, M., "Compact UWB bandnotch antenna with transmission-line-FED," Progress In Electromagnetics Research B, Vol. 3, 283-293, 2008.
doi:10.2528/PIERB07121407
11. Nedil, M. and T. A. Denidni, "Analysis and design of an ultra wideband directional coupler," Progress In Electromagnetics Research B, Vol. 1, 291-305, 2008.
doi:10.2528/PIERB07110704
12. Yin, X. C., C. Ruan, C. Y. Ding, and J. H. Chu, "A planar U type monopole antenna for UWB applications," Progress In Electromagnetics Research Letters, Vol. 2, 1-10, 2008.
13. Koo, B. W., M. S. Baek, and H. K. Song, "Multiple antenna transmission technique for UWB system," Progress In Electromagnetics Research Letters, Vol. 2, 177-185, 2008.
14. Khan, S. N., J. Hu, J. Xiong, and S. He, "Circular fractal monopole antenna for low VSWR UWB applications," Progress In Electromagnetics Research Letters, Vol. 1, 19-25, 2008.
doi:10.2528/PIERL07110903
15. Schmidl, T. M. and D. C. Cox, "Robust frequency and timing synchronization for OFDM," IEEE Trans. Commun., Vol. 45, No. 12, 1613-1621, 1997.
doi:10.1109/26.650240
16. Youhei, K., H. Hiratsuka, and S. Yukitoshi, Frequency offset compensation scheme for MB-OFDM by frequency spreading, Proc. of ISPACS 2005, 209-212, 2005.
17. Li, Y., T. Jacobs, and H. Minn, Frequency offset estimation for MB-OFDM-based UWB systems, Proc. of ICC 2006, 4729-4734, 2006.
18. Liu, S. and J. Chong, A study of joint tracking algorithms of carrier frequency offset and sampling clock offset for OFDM-based WLANs, Proc. of ICC 2002, 109-113, 2002.
19. Oberli, C. and B. Daneshrad, Maximum likelihood tracking algorithms for MIMO-OFDM, Proc. of ICC 2004, 2468-2472, 2004.
20. Li, C.-P., P.-L. Chen, and T.-T. Lin, Residual carrier frequency offset tracking for OFDM-based systems, Proc. of APCC 2004, 989-992, 2004.
21. Shi, K., E. Serpedin, and P. Ciblat, "Decision-directed fine synchronization for OFDM systems," IEEE Trans. Commun., Vol. 53, 408-412, 2005.
doi:10.1109/TCOMM.2005.843463
22. Wessman, M., A. Svensson, and E. Agrell, Frequency diversity performance of coded multiband-OFDM systems on IEEE UWB channels, Proc. of VTC 2004, 1197-1201, 2004.
23. Foerster, J., Channel modeling sub-committee report, IEEE 802.15-02/490r1-SG3a, 2003.