基于GPS和短波的高精度时钟系统研究与设计

Research and Design of High Precision Clock System Based on GPS and Short-wave Technology

摘要:

介绍了全球定位系统GPS、短波授时技术；在对高稳恒温晶振及其频率特性进行分析的基础上,设计了一种基于GPS卫星、短波无线电授时的高精度时钟系统；系统通过利用GPS接收处理模块、短波授时接收模块得到的秒脉冲信号、时间信息,经过信号检测,时延修正处理、性能优选,脉冲数量统计、脉冲滤波与卡尔曼算法处理、PWM脉冲调压控制,实现对高稳恒温晶振频率的校准,获得一个短期及长期频率准确度都比较优良的时间频率标准,同时利用校频后恒温晶振分频出的1 pps信号对RTC时间芯片进行校准,对外输出高精度时间信息；对恒温晶振校频系统的基本工作原理及关键技术进行了详细说明,试验结果表明,在时间不长于1 h内,频率准确度优于0.9*10-9；该系统实用方便,达到了将恒温晶振校准到较高指标的目的。

Abstract:

Introduced GPS, short-wave radio timing technology. Based on analysis of high stability constant temperature crystal and its frequency characteristics, design a high precision clock system based on GPS, short-wave radio-technology timing design. The system using GPS, short-wave receiving and processing module to get the second pulse signal, the time information, after signal check, delay correction, pulse select, pulse statistics , pulse filter and kalman arithmetic process, PWM voltage adjust, then get a standard second pulse signal, realize calibration of the crystal oscillator frequency, and obtain a short-term and long-term frequency stability are excellent time and frequency, at the same time using 1pps signal which is from constant temperature crystal to calibrate the time chip, after frequency correction, output a high precision time. Described the basic working principle and some module circuit, the experimental results show that, at the time of not more than 1 hour, frequency accuracy up to 0.9×10-9 , due to the method is practical and easy , this system will reach the aim of get higher index point of crystal oscillator calibrated. 