Abstract
The estimation of channel parameters, such as the fading amplitude and the power spectral density of the interference plus noise, is essential to the effective use of soft-decision decoding. Channel estimation may be implemented by the transmission of pilot signals that are processed by the receiver, but pilot signals entail overhead costs, such as the loss of data throughput. Deriving maximum-likelihood channel estimates directly from the received data symbols is often prohibitively difficult. There is an effective alternative when turbo or low-density parity-check codes are used. The expectation-maximization algorithm provides an iterative approximate solution to the maximum-likelihood equations and is inherently compatible with iterative demodulation and decoding. Two examples of advanced spread-spectrum systems that apply the expectation-maximization algorithm for channel estimation are described and analyzed in this chapter. These systems provide good illustrations of the calculations required in the design of advanced systems.
This is a preview of subscription content, log in via an institution to check access.
References
B. Levy, Principles of Signal Detection and Parameter Estimation. New York: Springer, 2008.
E. Kreyszig, Advanced Engineering Mathematics, 10th ed. Hoboken, NJ: Wiley, 2011.
Third Generation Partnership Project (3GPP); Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation, (Release 9), http://www.3gpp.org/ftp/Specs/archive/36_series/36.211/, 2010.
J. G. Proakis and M. Salehi, Digital Communications, 5th ed. New York: McGraw-Hill, 2008.
I. N. Psaromiligkos, S. N. Batalama, and M. J. Medley, “Rapid Combined Synchronization/Demodulation Structures for DS-CDMA Systems - Part I: Algorithmic Developments,” IEEE Trans. Commun., vol. 51, pp. 983 - 994, June 2003.
X. Wang and H. V. Poor, Wireless Communication Systems, Upper Saddle River, NJ: Prentice-Hall, 2004.
J. Choi, Adaptive and Iterative Signal Processing in Communications, Cambridge Univ. Press, 2006.
D. Torrieri, A. Mukherjee, and H. M. Kwon, “Coded DS-CDMA systems with Iterative Channel Estimation and No Pilot Symbols,” IEEE Trans. Wireless Commun., vol. 9, pp. 2012-2021, June 2010.
W. E. Ryan and S. Lin, Channel Codes: Classical and Modern. Cambridge, UK: Cambridge University Press, 2009.
T. M. Cover and J. M. Thomas, Elements of Information Theory, 2nd ed. Hoboken, NJ: Wiley, 2006.
D. Torrieri, S. Cheng, and M. C. Valenti, “Robust Frequency Hopping for Interference and Fading Channels,” IEEE Trans. Communications, vol. 56, pp. 1343-1351, Aug. 2008.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2011 Springer Science+Business Media, LLC
About this chapter
Cite this chapter
Torrieri, D. (2011). Systems with Iterative Channel Estimation. In: Principles of Spread-Spectrum Communication Systems. Springer, New York, NY. https://doi.org/10.1007/978-1-4419-9595-7_8
Download citation
DOI: https://doi.org/10.1007/978-1-4419-9595-7_8
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4419-9594-0
Online ISBN: 978-1-4419-9595-7
eBook Packages: EngineeringEngineering (R0)