基于星座点聚类和变换模式匹配的定时同步算法

Timing Synchronization Algorithm Based on Constellation Clustering and Transform Pattern Matching

定时同步技术是通信系统中的关键技术之一,传统的定时同步算法易受到频偏、噪声和数据相关性的影响,故有进一步提升同步性能的空间。可重构智能反射面(Reconfigurable Intelligent Surfaces,RIS)技术得到了学术界和产业界的广泛关注,可以有效地补盲和提升通信质量。基于智能反射面的调制技术被认为是一种新的调制架构,但是调制星座点分布往往不均匀。针对智能反射面调制星座点不均匀的问题,提出基于星座点聚类和变换模式匹配的定时同步算法,提升同步性能。提出的定时同步算法利用接收端星座点整体旋转而相对位置不变的特点,使用聚类方法提取出同步序列星座点的变换模式,然后进行本地相关找到同步点。仿真和实测系统均表明所提出的同步算法可以获得良好的同步性能。

Synchronization technology is one of the key technologies in communication systems.The traditional synchronization algorithm is easily affected by frequency offset,noise and data dependency,and the synchronization performance can be further improved.RIS(Reconfigurable Intelligent Surfaces)has raised wide concern in the academic community and the industry,and it can complement the blind area and improve the quality of communication effectively.Modulation scheme based on RIS is considered as a new modulation architecture,but the distribution of modulation constellations is often uneven,which will affect the synchronization performance.Therefore,this paper proposes a synchronization algorithm based on constellation clustering and transform pattern matching to improve the synchronization performance.The recieved constellations have the characteristic of overall rotation and invariable relative position.Therefore,the clustering method is used to extract the transformation mode of pilot constellation points,and the local correlation is performed to find the synchronization points.The simulation and experimental results show that the proposed synchronization algorithm can achieve a better synchronization performance.