基于数字锁相环的晶振频率同步模块设计

摘要

This paper designs a crystal oscillator synchronization system based on DLL to meet the demand of modem communications technology, radar technology, electronic measurement and some optoelectronic applications for high-stability and high-accuracy clocking requirements. This system contains a high resolution PFD based on FPGA delay line and a digital loop filter implemented in MiacroBlaze.And it adjusts the frequency of local crystal oscillator through a 16 bit DAC to make it synchronized with GPS pulse per second, which can get a high-stability and high-accuracy local clock.%为满足现代通信技术、雷达技术、电子测量以及光电应用领域对高稳定度高准确度时钟的要求,设计了一种基于数字锁相环的晶振同步系统.系统以基于FPGA数字延迟线的高分辨率鉴频鉴相器以及在MicroBlaze核中实现的卡尔曼数字环路滤波器为核心,通过16 bit DAC微调本地晶振振荡频率,使其同步于GPS秒脉冲,从而获得了高准确度高、稳定度的本地时钟.