A Scattered Pilot OFDM Receiver Employing Turbo ICI Cancellation in Fast Fading Environments

• SUYAMA Satoshi

  Tokyo Institute of Technology

• ITO Masafumi

  Tokyo Institute of Technology

• FUKAWA Kazuhiko

  Tokyo Institute of Technology

• SUZUKI Hiroshi

  Tokyo Institute of Technology

Abstract

This paper proposes a scattered-pilot-OFDM reception scheme employing turbo inter-carrier interference (ICI) cancellation in the fast varying fading environments of mobile communications. In the OFDM transmission, the orthogonality among the subcarriers cannot hold due to large Doppler shift, and the OFDM signal suffers from severe degradation due to ICI. The proposed receiver carries out two modes : (i) a coherent detection (CD) mode, and (ii) a turbo ICI cancellation (TC) mode. Initially, the receiver performs the CD mode. When any decision errors are detected, it shifts from the CD mode to the TC one that carries out both the ICI cancellation and the channel estimation by using the decoder output (the log likelihood ratio). In addition, the iteration of the TC mode can improve the accuracy of the channel estimation and ICI cancellation ability. Computer simulations following specifications for the mobile reception mode in the digital terrestrial television broadcasting demonstrate that the receiver can effectively cancel ICI due to the fast varying fading, and that its average BER performance is much better than that of CD.

Journal

• IEICE Trans. Commun., B

  IEICE Trans. Commun., B 88 (1), 115-121, 2005-01-01

  The Institute of Electronics, Information and Communication Engineers

Keywords

• OFDM
• mobile communications
• scattered-pilot
• turbo cancellation
• decision directed channel estimation
• digital terrestrial television broadcasting

Details

• CRID: 1571980077248847488
• NII Article ID: 110003222580
• NII Book ID: AA10826261
• ISSN: 09168516
• Text Lang: en
• Data Source:
  • CiNii Articles