A Cost Function for Joint Blind Equalization and Phase Recovery

In this paper a new cost function for blind equalization is proposed. The proposed cost function, referred to as the modified maximum normalized cumulant criterion (MMNC), is an extension of the previously proposed maximum normalized cumulant criterion (MNC). While the MNC requires a separate phase recovery system after blind equalization, the MMNC performs joint blind equalization and phase recovery. To achieve this, the proposed algorithm maximizes a cost function that considers both amplitude and phase of the equalizer output. The simulation results show that the proposed algorithm has an improved channel equalization effect than the MNC algorithm and simultaneously can correct the phase error that the MNC algorithm is unable to do. The simulation results also show that the MMNC algorithm has lower complexity than the MNC algorithm. Moreover, the MMNC algorithm outperforms the MNC algorithm particularly when the symbols block size is small.

Authors:

• Reza Berangi
• Morteza Babaee
• Majid Soleimanipour

Keywords:

• Blind equalization
• maximum normalized cumulant criterion (MNC)
• intersymbol interference (ISI)
• modified MNC criterion (MMNC)
• phase recovery.

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