中文摘要：

针对相位噪声造成的卫星数传系统性能的下降,该文仿真分析了2种不同频段下的相位噪声对于未编码和有低密度奇偶校验（low-density parity-check,LDPC）码的高阶调制系统的影响,并针对较高频段相位噪声造成的编码系统性能的明显下降,提出了一种联合LDPC译码的相位噪声迭代补偿算法。该算法通过对比解调前与译码后符号的相位信息差异,利用相位噪声的窄带低通特性对其进行提取,进而通过构造迭代环路对解调前的符号进行补偿。仿真结果表明：该算法可以有效降低误比特率,对于因相位噪声引起的LDPC编码系统性能的下降有显著的改善作用。

英文摘要：

Phase noise can impair the BER performance of high-data-rate satellite communications. The influence of the phase noise varies in the two frequency hands in both the uncoded or low-density parity-check （LDPC） coded communication systems. This paper presents a simulation and then an iterative compensation algorithm for the LDPC codes for the phase noise in the higher frequency band, which significantly degrades the high order modulation systems performance, The algorithm first compares the phases of the receiving and after-decoding symbols, extracts the difference based on the low-pass and narrow-band characteristics of the phase noise, and their compensates for the losses in an iteration loop. Simulations show that the method improves the LDPC-coded systems performance when the phase noise significantly degrades the signal.