Blind Channel Estimation Based on the Lloyd-Max Algorithm in Narrowband Fading Channels and Partial-Band Jamming

Dizdar O., YILMAZ A. Ö.

IEEE TRANSACTIONS ON COMMUNICATIONS, vol.60, no.7, pp.1986-1995, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 60 Issue: 7
  • Publication Date: 2012
  • Doi Number: 10.1109/tcomm.2012.051712.110523
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1986-1995
  • Keywords: Blind channel estimation, Lloyd-Max, fading, narrowband, jamming, jammer detection, ITERATIVE DEMODULATION, SERIAL CONCATENATION, EQUALIZATION, PSK
  • Middle East Technical University Affiliated: Yes


In wireless communications, knowledge of the channel coefficients is required for coherent demodulation. In this work, a blind channel estimation method based on the Lloyd-Max algorithm is proposed for single-tap fading channels. The algorithm estimates the constellation points for the received signal using the Lloyd-Max algorithm. The algorithm is investigated for frequency hopping systems with small hop durations and operating under partial-band jamming for both detecting the jammer and estimating the channel. The performance of the Lloyd-Max channel estimation algorithm is compared to the performance of pilot-based channel estimation algorithms and non-coherent demodulation and decoding. A special concatenated channel code is constructed to work with the proposed blind channel estimation due to the phase ambiguity in estimates.