Iterative demodulation and decoding has been introduced in 2005 by Colavolpe, Barbieri, and Caire to cope with channels affected by phase noise. However, iterations between the channel decoder and the demodulator increase system’s complexity. In this letter, we propose an iterative carrier recovery scheme where the current iteration is based on the hard decisions taken after the previous iteration. The resulting algorithm is easy-to-implement and offers excellent phase noise tracking performance, as demonstrated by the numerical results presented in the letter that are obtained with phase noise generated by linewidths of practical interest and a highly spectral efficient modulation scheme as 256-QAM.

中文翻译：

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迭代前馈解调和阈值检测

为了应对受相位噪声影响的信道，Colavolpe，Barbieri和Caire于2005年引入了迭代解调和解码。但是，通道解码器和解调器之间的迭代会增加系统的复杂性。在这封信中，我们提出了一种迭代的载波恢复方案，其中，当前迭代基于前一次迭代后做出的硬性决策。所产生的算法易于实现，并且具有出色的相位噪声跟踪性能，如信中所示的数值结果所示，该结果是由具有实际意义的线宽和256-QAM的高效频谱高效调制方案所产生的相位噪声获得的。