80MHz低相位噪声晶体振荡器的设计与实现
发布时间：2018-09-17 12:42
【摘要】：本文从实际需要出发,以如何设计低相位噪声晶体振荡器为研究课题,分析了晶体振荡器相位噪声产生的机理,并探寻了一种新的仿真方法,通过该仿真方法指导的晶体振荡器的设计,达到了很好的相位噪声指标。本文的工作有:1)深入分析了反馈式振荡器的工作原理,分别得出了振荡器振荡的相位稳定和幅值稳定条件,然后以复数振荡方程为计算工具,着重分析了巴特勒振荡电路的工作原理。之后确定了本课题的谐振器选用SC切型,选取巴特勒共基串联振荡电路作为主振电路。随后基于经典Leeson模型,重点分析了巴特勒振荡器的相位噪声,并利用无源网络推导出了LQ的表达式,通过MATLAB计算得出LQ和2C的关系曲线,得出在两者之间合理折中可以降低相位噪声的结论,为接下来的课题设计奠定理论基础。2)介绍了ADS仿真软件以及谐波平衡仿真基础,首先给出了使用ADS理想模型进行仿真的振荡器相位噪声曲线,通过跟理论相位噪声谱结构的比较分析,得出仿真出现错误的原因是由于没有考虑非线性器件噪声的影响,于是探寻了一种新的仿真方法,即建立晶体管的非线性模型,再次进行仿真后,得到了考虑非线性器件影响之后的相位噪声仿真曲线,并且通过与理论相位噪声谱结构的比较证实了该仿真方法的正确性,对接下来振荡器的设计提供了指导。3)对晶体振荡电路的噪声来源进行挖掘,在分析的基础上给出了低噪声晶振的设计原则,设计了频率为80MHz的低相位噪声晶体振荡器。课题研究的最后,制作出80MHz低相位噪声晶体振荡器的样机,然后使用Agilent E5052B信号源分析仪实际测试了该晶体振荡器的相位噪声,测得相位噪声水平为:-140dBc/Hz@100Hz,符合设计要求,并通过与国际上相近频率范围内振荡器相位噪声指标的比较,论证了该方法的价值,完成了本课程的设计。
[Abstract]:In this paper, the mechanism of phase noise generation of low phase noise crystal oscillator is analyzed, and a new simulation method is explored, which is based on the practical needs and how to design a low phase noise crystal oscillator. The design of the crystal oscillator guided by the simulation method achieves a good phase noise index. In this paper, the working principle of the feedback oscillator is deeply analyzed, and the phase stability and amplitude stability conditions of the oscillator are obtained, respectively. Then the complex oscillation equation is used as the calculation tool. The working principle of Butler oscillating circuit is analyzed emphatically. Then the SC tangent type of resonator and Butler common base series oscillator circuit are selected as the main oscillator circuit. Based on the classical Leeson model, the phase noise of Butler oscillator is analyzed, and the expression of LQ is derived by using passive network. The relation curve between LQ and 2C is calculated by MATLAB. The conclusion that the phase noise can be reduced by a reasonable compromise between the two is obtained. The theoretical foundation for the next project design is established. (2) the ADS simulation software and the harmonic balance simulation foundation are introduced. First, the phase noise curve of the oscillator simulated by ADS ideal model is given. By comparing with the theoretical phase noise spectrum structure, it is concluded that the reason of the error in the simulation is that the influence of nonlinear device noise is not taken into account. A new simulation method, that is, the nonlinear model of transistors is established, and the phase noise simulation curve considering the influence of nonlinear devices is obtained after the simulation is done again. The correctness of the simulation method is verified by comparing with the theoretical phase noise spectrum structure, and the design of the oscillator is guided by .3) the noise source of the crystal oscillation circuit is excavated. Based on the analysis, the design principle of low noise crystal oscillator is given, and the low phase noise crystal oscillator with frequency of 80MHz is designed. Finally, a prototype of 80MHz low phase noise crystal oscillator is made, and the phase noise of the crystal oscillator is tested by using Agilent E5052B signal source analyzer. The phase noise level is measured to be: -140 dBc / Hzr 100 Hz, which meets the design requirements. The value of this method is proved by comparing with the phase noise index of oscillator in the similar frequency range of the world, and the design of this course is completed.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN752
本文编号：2245961
[Abstract]:In this paper, the mechanism of phase noise generation of low phase noise crystal oscillator is analyzed, and a new simulation method is explored, which is based on the practical needs and how to design a low phase noise crystal oscillator. The design of the crystal oscillator guided by the simulation method achieves a good phase noise index. In this paper, the working principle of the feedback oscillator is deeply analyzed, and the phase stability and amplitude stability conditions of the oscillator are obtained, respectively. Then the complex oscillation equation is used as the calculation tool. The working principle of Butler oscillating circuit is analyzed emphatically. Then the SC tangent type of resonator and Butler common base series oscillator circuit are selected as the main oscillator circuit. Based on the classical Leeson model, the phase noise of Butler oscillator is analyzed, and the expression of LQ is derived by using passive network. The relation curve between LQ and 2C is calculated by MATLAB. The conclusion that the phase noise can be reduced by a reasonable compromise between the two is obtained. The theoretical foundation for the next project design is established. (2) the ADS simulation software and the harmonic balance simulation foundation are introduced. First, the phase noise curve of the oscillator simulated by ADS ideal model is given. By comparing with the theoretical phase noise spectrum structure, it is concluded that the reason of the error in the simulation is that the influence of nonlinear device noise is not taken into account. A new simulation method, that is, the nonlinear model of transistors is established, and the phase noise simulation curve considering the influence of nonlinear devices is obtained after the simulation is done again. The correctness of the simulation method is verified by comparing with the theoretical phase noise spectrum structure, and the design of the oscillator is guided by .3) the noise source of the crystal oscillation circuit is excavated. Based on the analysis, the design principle of low noise crystal oscillator is given, and the low phase noise crystal oscillator with frequency of 80MHz is designed. Finally, a prototype of 80MHz low phase noise crystal oscillator is made, and the phase noise of the crystal oscillator is tested by using Agilent E5052B signal source analyzer. The phase noise level is measured to be: -140 dBc / Hzr 100 Hz, which meets the design requirements. The value of this method is proved by comparing with the phase noise index of oscillator in the similar frequency range of the world, and the design of this course is completed.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN752
【共引文献】
相关博士学位论文 前1条
1 徐卫林;无线射频通信片上系统的压控振荡器与电源管理的研究[D];武汉大学;2011年
相关硕士学位论文 前1条
1 朱成辉;用于条纹相机的同步扫描电路设计[D];西安电子科技大学;2014年
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