EM-based channel estimation for coded multi-carrier transmissions

Yang Liu, Loïc Brunel, Joseph Boutros

Research output: Contribution to journalArticle

6 Citations (Scopus)


Expectation-maximization (EM) based iterative algorithms are investigated in order to estimate the impulse response of a frequency-selective multipath channel in a coded OFDM system. Two ways of choosing the EM complete data are compared: a complete data built from observations and transmitted symbols (CL-EM) and a complete data chosen by decomposing noise and observation components (NCD-EM). Both CL-EM and NCD-EM algorithms are derived for a coded OFDM system. The rate of convergence of both EM algorithms is theoretically determined. It is found that the rate of convergence of CL-EM is independent from the number of channel taps at high signal-to-noise ratio (SNR), while that of NCD-EM varies with the number of taps. It is shown that CL-EM converges in a few iterations. Furthermore, considering the complexity per iteration, CL-EM has a lower complexity than its counterpart. We also establish a Cramer-Rao bound (CRB) for coded OFDM transmission. Simulation results show that CL-EM has a good performance-complexity trade-off and it achieves the CRB.

Original languageEnglish
Article number5989892
Pages (from-to)3185-3195
Number of pages11
JournalIEEE Transactions on Wireless Communications
Issue number10
Publication statusPublished - 1 Oct 2011



  • channel estimation
  • Cramer-Rao bound
  • expectation maximization
  • Orthogonal frequency-division multiplexing
  • rate of convergence

ASJC Scopus subject areas

  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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