高阶QAM信号多状态自适应卡尔曼滤波载波同步算法

发布时间：2018-01-09 23:01

本文关键词：高阶QAM信号多状态自适应卡尔曼滤波载波同步算法　出处：《信号处理》2014年06期 　论文类型：期刊论文

【摘要】：通信信号盲载波恢复是非协作模式下接收方解调的关键环节之一。为提高频偏捕获范围与速度,同时有效增强算法跟踪时变频偏能力,本文针对正交幅度调制(QAM)信号,通过理论推导得出滤波器环路带宽的变化特性,提出一种基于自适应判决引导扩展卡尔曼滤波的载波同步算法。该算法在现有卡尔曼滤波载波同步算法的基础上,引入多状态自适应切换机制自适应地改变滤波器参数,并依据实验测试数据分析得出调整原则并完成滤波器参数的选取。理论分析和仿真表明,与已有的卡尔曼载波同步算法及二阶数字锁相环算法相比,该算法不仅捕获速度更快范围更大,且能在存在时变多普勒频移的情况下较好地跟踪时变频偏和相位,在大频偏条件下的算法跟踪性能与鲁棒性等方面均有优势。
[Abstract]:Blind carrier recovery of communication signals is one of the key links of receiver demodulation in non-cooperative mode. In order to improve the range and speed of frequency offset acquisition, it also effectively enhances the frequency conversion offset ability of algorithm tracking. In this paper, for the quadrature amplitude modulation (QAM) signal, the variation characteristics of filter loop bandwidth are obtained by theoretical derivation. A carrier synchronization algorithm based on adaptive decision guided extended Kalman filter is proposed, which is based on the existing Kalman filter carrier synchronization algorithm. The multi-state adaptive switching mechanism is introduced to adaptively change the filter parameters, and according to the experimental test data analysis, the adjustment principle is obtained and the filter parameters are selected. Theoretical analysis and simulation show that. Compared with the existing Kalman carrier synchronization algorithm and the second-order digital phase-locked loop algorithm, this algorithm not only has a faster capture speed, but also has a larger range. The algorithm can track the frequency conversion offset and phase better when there is time-varying Doppler frequency shift. The algorithm has advantages in tracking performance and robustness under the condition of large frequency offset.
【作者单位】：解放军信息工程大学信息工程学院;
【基金】：河南省自然科学基金资助项目(0611051400) 河南省基础与前沿基金资助项目(082300413205)
【分类号】：TN919.34
【正文快照】： 1引言正交幅度调制(QAM)以其较高的频带利用率,被广泛应用于通信系统[1]。在非协作通信模式下,如何快速准确实现载波盲同步就成为接收解调及后续处理所要解决的关键问题及难点所在。为有效跟踪接收信号的频率,目前接收机大多使用锁相环(PLL)技术[2-4]。判决引导PLL结构简单,但

【参考文献】