Joint Blind Equalization & Carrier Phase Recovery based on Adaptively Varying Modulus Algorithm (AVMA)

The blind adaptive equalization and identification of communication channels is an important theoretical and practical problem which attracts much attention in recent years. Due to its robustness and easy implementation, constant modulus algorithm (CMA) is an excellent choice to correct the distortions caused by transmission channels. In two dimensional communication systems, however, phase recovery is a serious issue which can not be handled by conventional CMA due to its phase blind nature. In this paper, a new algorithm that jointly performs the blind channel equalization and carrier phase recovery simultaneously based on adaptively varying the real and imaginary components of the modulus of the received signal is proposed. The results obtained by simulation confirm the effectiveness of the proposed algorithm in clustering the equalized signals, recovering and correcting the carrier phase shift and removing LSI for the case of 16-QAM signal constellation