Convergence behavior of iterative equalization and decoding schemes with equalization and memory

In recent years, there has been a growing interest in applying turbo algorithms to enhance performance in communication systems. Among them, iterative equalization and decoding, turbo equalization, has proven to be a powerful technique to mitigate intersymbol interference. In this paper, we propose a soft interference canceler with memory, suitable for general complex symbol alphabets, as part of a turbo equalization scheme and investigate its convergence behavior using the extrinsic information transfer (EXIT) chart tool. Although the true behavior of the trajectory of the iterative process cannot be perfectly predicted, we obtain useful information to reduce computational complexity of the turbo scheme.