基于双环系统的细步进频率合成器  

A Fine Step Frequency Synthesizer Based on Double Loop System

作　　者：沈文渊[1] 唐光庆 杨清福 穆晓华[1] 李庆洪[1] 蒋创新[1] SHEN Wenyuan;TANG Guangqing;YANG Qingfu;MU Xiaohua;LI Qinghong;JIANG Chuangxin(The 26th Institute of China Electronics Technology Group Corporation,Chongqing 400060,China;Military Representative Office of Air Force Equipment Department in Chongqing,Chongqing 400060, China)

机构地区：[1]中国电子科技集团公司第二十六研究所,重庆400060 [2]空军装备部驻重庆地区军事代表室,重庆400060

出　　处：《压电与声光》2020年第2期173-177,共5页Piezoelectrics & Acoustooptics

摘　　要：针对小数分频锁相的整数边带杂散问题提出了一种基于双环系统的细步进频率合成方法。根据变参考抑制小数分频整数边带杂散的工作原理,采用一级整数分频锁相环与一级小数分频锁相环级联的方法共同构成细步进频率合成系统,通过软件算法调整第一级锁相环的N分频值和M参数,最终实现全频段杂散指标最优。结果表明,根据该方法设计的宽带(带宽为4~8 GHz)、细步进(1 kHz)的频率合成器,其实测杂散优于75 dBc,相位噪声在1 kHz处优于-96 dBc/Hz,跳频时间小于47μs。A fine step frequency synthesis method based on double loop system is proposed to solve the integer sideband spur problem of fractional frequency division phase lock.According to the working principle of variable reference to suppress fractional frequency integer sideband spurs,a fine step frequency synthesis system is formed by cascading a first-order integer frequency division phase-locked loop(PLL)and a first-order fractional frequency division PLL.The N frequency division and M parameters of the integer PLL are adjusted through software algorithms,and finally the full frequency band spurs index is optimized.A broadband(bandwidth:4-8 GHz)fine step(1 kHz)frequency synthesizer is designed according to the proposed method.The measured spurs is better than 75 dBc,phase noise is better than-96 dBc/Hz at 1 kHz,and frequency hopping time is less than 47μs.

关 键 词：锁相环(PLL) 小数分频 频率合成器 整数边带 相位噪声 

分 类 号：TN65[电子电信—电路与系统]