宽锁定范围锁相环频率合成器稳定特性研究

项目名称： 宽锁定范围锁相环频率合成器稳定特性研究

项目编号： No.61204028

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 信息四处

项目作者： 刘艳艳

作者单位： 南开大学

项目金额： 28万元

中文摘要： 稳定性是确保频率合成器实用化的关键。目前一般采用的Best锁相环频率合成器设计方法仅适用窄带系统，对于各种非理想因素采取了忽略或近似的处理手段。但在实际情况中，特别是在宽频率范围应用条件下，系统参数随分频值变化较大，延迟等非理想因素亦会对系统稳定性产生较大的影响，根据上述理论所得的稳定性分析结果将出现严重误差。 本项目基于自动控制理论的基本原理，结合电路模块的行为特点，深入考察宽频率范围下系统参数的变化及其对稳定性的影响；通过分析环路延迟的来源，研究小数延迟在离散域合理精确的描述方式，定量评估环路延迟对锁相环频率合成器稳定性的恶化作用；进而形成预测宽锁定范围频率合成器系统稳定范围的系统方法，指导频率合成器优化设计。本项目研究具有创新性，将为进一步提升频率合成器产品性能，增强实用性提供指导。

中文关键词： 频率合成器；稳定性；宽锁定范围；小数延迟；

英文摘要： Stability is a critical issue for the application of frequency synthesizers. The common design method suggested by Best and et al., which neglects or deals with non-ideal factors approximately, can only provide the basic understanding for narrow band phase-locked loop (PLL) systems. However, in practice, especially in the wide band application, the parameters of the system change as the variety of the dividing ratio. In addition, many non-ideal factors, such as the loop delay, may affect the stability of the system significantly. Therefore the stability analysis based on above theory will have a serious deviation. This project bases on fundermantal principles of the automatic control theory. According to the behavioral characteristics of the circuit blocks, we will explore the change of the system parameters and their impact on the stability in the wide band condition. By studying the delay in the feedback loop, an apropriate and more accurate z-domain model for the fractional delay will be proposed, and its effect on the stability of the system will be evaluated quantitatively. Furthermore, we will present a systematic method to forecast the stability limit of the wide locking range frequency synthesizers. The reserch is innovative, and the achievement will be helpful to improve the performance of the frequency

英文关键词： Frequency Synthesizer；Stability；Wide Locking Range；Fractional Delay；