New Blind Algorithms Based on Modified “Constant Modulus” Criteria for QAM Constellations

  • C. A. R. Fernandes
  • J. C. M. Mota
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3124)


This work presents a family of new algorithms aiming to perform blind equalization in Quadrature Amplitude Modulation (QAM) signals. The algorithms are based on modified Constant Modulus (CM) criteria and they use decision direction. One of the proposed algorithms is based on the Constant Modulus Algorithm (CMA). Another one is based on the Recursive CMA (RCMA). The other two ones are dual-mode versions for high-level modulations. The first mode is used to avoid a too large number of incorrect decisions. Computer simulations show they outperform the CM based algorithms.


Blind equalization decision-directed constant modulus dual-mode 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • C. A. R. Fernandes
    • 1
  • J. C. M. Mota
    • 1
  1. 1.Departamento de Engenharia de Teleinformática (DETI)Universidade Federal do Ceará (UFC)FortalezaBrazil

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