Open Access Open Access  Restricted Access Subscription or Fee Access

Practical Channel Estimation for Rapidly Varying Signals in OFDM Systems

Manasvi Patil, Achala Deshmukh

Abstract


This paper proposes a novel pilot-aided algorithm for estimation of rapidly varying wireless channels in OFDM systems. This approach is specifically designed for channels varying on the scale of a single OFDM symbol duration. From the pilot information, we recover information about the channel taps in the framework of the Basis Expansion Model (BEM). In this paper explicit formulas for the BEM coefficients in terms of the receive signal are derived. For a system with L channels taps, our method uses (Llog L) operations and � (L) memory per OFDM symbol.

Keywords


Channel Estimation, OFDM, Time Varying Channels, Basis Expansion Model, Channel Taps.

Full Text:

PDF

References


E. Haas, “Aeronautical channel modeling," IEEE Trans. Veh. Technol.,vol. 51, no. 2, pp. 254–264, Mar. 2002.

S. Colieri, M. Ergen, A. Puri, and A. Bahai, “Channel estimation techniques based on pilot arrangement in OFDM systems,” IEEE Trans. Broadcast., vol. 48, no. 3, pp. 223–229, Sep. 2002.

Z. Tang, R. C. Cannizzaro, G. Leus, and P. Banelli, “Pilot-assisted timevarying channel estimation for OFDM systems," IEEE Trans. Signal Process., vol. 55, no. 5, pp. 2226–2238, May 2007.

T. Zemen and C. F. Mecklenbrauker, “Time-variant channel estimation using discrete prolate spheroidal sequences," IEEE Trans. Signal Process., vol. 53, no. 9, pp. 3597–3607, Sep. 2005.

Z. Tang and G. Leus, “Pilot schemes for time-varying channel estimation in OFDM systems," in Proc. IEEE Workshop Signal Process. Advances Wireless Commun., June 2007, pp. 1–5.

C. Shin, J. G. Andrews, and E. J. Powers, “An efficient design of doubly selective channel estimation for OFDM systems," IEEE Trans. Wireless Commun., vol. 6, no. 10, pp. 3790–3802, Oct. 2007.

H. A. Cirpan and M. K. Tsatsanis, “Maximum likelihood blind channel estimation in the presence of Doppler shifts," IEEE Trans. Signal Process., vol. 47, no. 6, pp. 1559–1569, June 1999.

M. Guillaud and D. T. M. Slock, “Channel modeling and associated inter-carrier interference equalization for OFDM systems with high doppler spread," in Proc. IEEE Int. Conf. Acoustics, Speech, Signal Process., Apr. 2003, vol. 4, pp. 237–240.

T. Zemen, C. F. Mecklenbrauker, and R. R. Müller, “Time variant channel equalization for MC-CDMA via Fourier basis functions," in Proc. MC-SS Workshop, 2003, pp. 451–458.

G. Leus, “On the estimation of rapidly varying channels," in Proc European Signal Process. Conf., Sep. 2004, vol. 4, pp. 2227–2230.

T. Zemen and C. F. Mecklenbrauker, “Time-variant channel equalization via discrete prolate spheroidal sequences," in Proc. 37th Asilomar Conf. Signals, Syst. Computers, Nov. 2003, vol. 2, pp. 1288–1292.

D. K. Borah and B. T. Hart, “Frequency-selective fading channel estimation with a polynomial time-varying channel model," IEEE Trans.Commun., vol. 47, no. 6, pp. 862–873, June 1999.

A. P. Kannu and P. Schniter, “MSE-optimal training for linear timevarying channels," in Proc. IEEE Int. Conf. Acoustics, Speech, Signal Process., vol. 3, Mar. 2005.

M. Schwartz, W. Bennett, and S. Stein, Communication Systems and Techniques. Wiley-IEEE Press, 1995.

M. Schwartz, W. Bennett, and S. Stein, Communication Systems and Techniques. Wiley-IEEE Press, 1995.

R. Buehrer, “Code division multiple access (CDMA)," Synthesis Lectures Commun., vol. 1, no. 1, pp. 1–192, 2006.

Draft IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems, IEEE Draft Std 802.16e/D7, 2005.

P. Schniter, “Low-complexity equalization of OFDM in doubly selective channels," IEEE Trans. Signal Process. [see also IEEE Trans. Acoust., Speech, Signal Process.], vol. 52, no. 4, pp. 1002–1011, Apr. 2004.

K. Fang, L. Rugini, and G. Leus, “Low-complexity block transmission over doubly selective channels: iterative channel estimation and turbo equalization,” EURASIP J. Advances Signal Process., vol. 2010.

T. Hrycak, S. Das, G. Matz, and H. Feichtinger, “Low complexity equalization for doubly selective channels modeled by a basis expansion," IEEE Trans. Signal Process., vol. 58, no. 11, pp. 5706–5719, 2010.

D. Gottlieb and C.-W. Shu, “On the Gibbs phenomenon and its resolution," SIAM Review, vol. 39, no. 4, pp. 644–668, 1997.

E. Tadmor, “Filters, mollifiers and the computation of the Gibbs phenomenon," Acta Numer., vol. 16, pp. 305–378, 2007.

T. Driscoll and B. Fornberg, “A Pade-based algorithm for overcoming the Gibbs phenomenon," Numer. Algorithms, vol. 26, no. 1, pp. 77–92, 2001.


Refbacks

  • There are currently no refbacks.


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