基于抛物线内插的位定时算法研究

Research on Bit Timing Algorithm Based on Parabolic Interpolation

位定时同步是数字通信接收机的重要组成部分,定时同步的准确性直接影响整个系统的性能。突发通信一般采用数据辅助的前馈式位定时同步结构。针对突发通信短时的特点,搭建了一种基于抛物线内插的位定时同步估计的低复杂度算法。该算法仅需利用信息帧头捕获到相关锋;然后,根据抛物线误差估计算法对当前采样信号进行误差估计,再选取合适的插值滤波器进行插值计算,获得最佳采样点,从而实现突发信号的定时同步过程。结果表明,该算法实现简单,在低信噪比的情况下,能够满足突发信号快速实现定时同步的需求,且其性能仍接近克拉美罗界。

Bit timing synchronization is an important part of digital communication receivers,and the accuracy of timing synchronization directly affects the performance of the whole system.A data-assisted feed-forward bit timing synchronization structure is generally adopted for burst communication.A lowcomplexity algorithm based on parabolic interpolation for bit timing synchronization estimation is constructed for the short-time characteristics of burst communication.The algorithm only needs to capture the relevant fronts using the information frame header;then,estimates the error of the current sampled signal according to the parabolic error estimation algorithm;finally,selects a suitable interpolation filter for interpolation calculation to obtain the optimal sampling point,thus achieving the timing synchronization process of the burst signal.Simulation results indicate that the algorithm is simple to implement,and in the case of low signal-to-noise ratio,it is able to meet the need for fast timing synchronization of burst signals,and its performance is still close to the Clamello boundary.