摘要
研究了小波调制解调系统码元同步信息的提取方法。分别利用小波函数的相关性及尺度函数的相关性构造了两种新的同步环算法,由算法构造的环路分为捕获和跟踪两部分,可以精确估计小波调制信号相位延时,跟踪收发时钟的频偏。算法通过对相位误差函数的修正,改善了同步环路的收敛性能,提高了环路抗假锁能力。在高斯信道下仿真表明,两种同步算法均可较好克服假同步,但基于尺度函数的同步环路稳定性更好,而基于小波函数的环路收敛速度更快。
The clock synchronization algorithm for timing recovery in wavelet-based multirate system is studied. Based on the orthogonal property of the wavelet function and the scaling function, two kinds of the clock synchronization algorithm by using a novel improved S-curve. And then, the corresponding novel frequency and phase tracking locked loops are proposed. The algorithm has some excellent characteristics, such as a coherent phase and frequency synchronization, a fast capture time, an enhanced stable convergence and so on. The loop can realize dual functions of the frequency lock and the coherent phase synchronization. The fundamental characteristics of the algorithm are discussed. Simulation results show that the approach can estimate the correct timing point, but the loop based on the wavelet function converges faster, and the loop based on the scaling function is stable.
出处
《数据采集与处理》
CSCD
北大核心
2007年第2期144-149,共6页
Journal of Data Acquisition and Processing
基金
空间微波国家重点实验室预研基金(51473030105JB3201)资助项目
关键词
最大似然估计
小波调制
时钟同步
相位误差函数
maximal likelihood
wavelet-based modulation
clock synchronization
phase errorfunction
