长波授时系统相位跟踪点检测的数字化研究  

Digitization Research on Detection of the Phase Tacking Point in Long Wave Time Service Systems

作　　者：邹德财[1] 边玉敬[1] 吴海涛[1] 李云[1] 

机构地区：[1]中国科学院国家授时中心

出　　处：《西安交通大学学报》2006年第6期729-733,共5页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(10443001).

摘　　要：为了实现长波授时系统接收机的数字化，提高检测效率，对接收到的100kHz长波信号进行1MHz指定频率的采样，充分研究天波对地波信号的影响，找出相位跟踪点与被检测信号的几何关系，提出了一种用数字方式确定相位跟踪点的周期累加值算法．与传统的检测方式相比，该算法基于现场可编程逻辑器件（FPGA）实现，采用大量采样数据代替传统的单个峰值，实现了天波与地波的检测分离，并在运行的同时给出了协调世界时秒信息．采用FPGA相关工具的仿真结果表明，该算法能够有效地消除噪声与天波的干扰，在数字滤波后信号的信噪比高于21．6dB时，该算法能达到0．0％～0．4％的低失误率．A cycle-addition value algorithm for the detection of the phase tracking point using digital method was proposed in order to actualize the digitization of receiver for the long wave time service system and improve the efficiency of detection. The received 100 kHz long wave signals are sampled with specified 1 MHz and the influence of the sky-wave on the ground-wave is investigated fully to find out the geometrical relationship between the phase tracking point and the detected signal. Compared with the conventional method, the advantage of the algorithm is that it is realized with field programmable gate array（FPGA） chip and the conventional single peak value is replaced by a large number of sampled data. The ground-wave is separated from the sky-wave and the second information of coordinated universal time is provided while running the new algorithm. The simulation results through the related tool of FPGA show that the interference of the sky-wave and the noise can be eliminated effectively by this method. The low error-rate of 0.0% to 0.4% can be achieved compared to the conventional methods when signal-to-noise ratio is higher than 21.6 dB after digital filtering.

关 键 词：长波授时系统 天波 周期累加值 协调世界时 

分 类 号：TN96[电子电信—信号与信息处理]