摘要
设计了一种支持点频、脉内线性调频、频率捷变的雷达通用型频率源方案。利用双DDS克服了单DDS无法同时兼顾频率捷变和线性调频的缺陷,通过有效的频率规划,解决了双DDS相互干扰的问题,具有良好的相噪杂散性能,支持多普勒频移、脉内线性调频时间、带宽、斜率参数均可大范围小步进灵活配置。整个组件形成模块化,适用于扩展成不同频段、不同模式的多普勒雷达频率源及其目标模拟器,并给出了一种毫米波段扩展方案。实测结果表明,系统在725~775MHz输出带宽范围内可按照50Hz的频率步进任意设置中心频点和频率捷变范围,多普勒频移分辨率为1Hz,脉内线性调频斜率正负可设置,调频时间和带宽可在4~4 000μs和100kHz^40MHz按照最小步长4ns和5Hz任意设置,捷变频时间小于890ns。
A general radar frequency synthesizer scheme is designed in this paper,which supports tone frequency,linear frequency modulation and frequency agility.The double DDS are used for overcoming the defect of single DDS not supporting frequency agility and linear frequency modulation at the same time.The interference problem was solved between the two DDS through effective frequency planning,while good performance on phase noise and spurious is achieved.The time,bandwidth,slope of linear frequency modulation and the Doppler frequency shift can be configured flexibly in large range and small step.The whole part is modularized suitable for extending to different frequency bands and modes of the frequency synthesizers of Doppler radars and their target simulators.A expansion scheme of millimeter wave band is given.The experimental results show that the output frequency range is 725-775MHz,the center and hopping frequency can be set by the 50 Hz step,and the resolution of Doppler frequency is 1Hz.The slope of linear frequency modulation signal can be set to be positive or negative,the time of linearly frequency modulated can be set in the range of 4-4 000μs,and its minimal step is 4ns.The bandwidth of linear frequency modulation can be set in the range of 100kHz-40MHz,and its minimal step is 5Hz,the hopping time is less than 890 ns.
出处
《雷达科学与技术》
北大核心
2016年第4期427-432,共6页
Radar Science and Technology
关键词
雷达技术
频率合成
线性调频
频率捷变
参数可配置
radar technology
frequency synthesis
LFM
frequency agility
configurable parameters
