相位噪声精密测量新技术

发布时间：2018-04-05 04:00

本文选题：相位重合检测　切入点：相位抖动　出处：《西安电子科技大学》2014年硕士论文

【摘要】：相位噪声是衡量频率标准源和现代电子设备的重要技术指标,在基本频率源的特性的研究以及性能的测试中的重要性日益增加。本文根据周期信号间的相位周期性变化规律,利用相位重合检测技术,实现了高分辨率的相位噪声测量。通过对周期性信号间的相位关系的深入研究,为相位重合检测模糊区提供了理论的基础。重合检测电路的设计中,由于相位重合检测线路存在一定的分辨率,在输入的两信号的相位差小于一定的值时,实现了重合脉冲的输出。该技术能够实现利用单一的参考源就可完成宽范围内的任意频率信号的的快响应时间、高分辨率的相位噪声测量,不同于传统的基于复杂电路设计的相位噪声测量系统,不仅节约了成本,而且提高了测量精度。相位噪声的测量分为近端和远端之分,具体设计如下:1、在近端相位噪声测量系统设计中,其原理是通过对闸门内计数值的起伏变化,利用对相位重合点之间的信号进行无间隙计数及重合脉冲簇的包络状况来提取相位抖动,经过间接的转换方式,最终实现将相位抖动转换为单边带相位噪声。2、对于远端相位噪声的测量,本文提出了基于相位重合检测模糊区特征的相位噪声测量方法,这是一种全新的测量方法。在参考和被测信号的标称频率相同或者成倍数并带有微小偏差时,两信号间的相位差变化的单调性,所以这些重合脉冲是集中出现的,呈现出一种包络形状的模糊区。重合检测线路的分辨率是稳定的,所以重合检测模糊区是相对稳定的。同时,模糊区又存在着细微的变化,这是由相位噪声引起的。因此,利用重合检测模糊区可以提取噪声引起的相位抖动信息。维纳辛钦定理是实现相位噪声测量的算法基础,这个定理描述了从相位抖动转化为相位噪声的过程,其中经历了自相关和快速傅立叶变换。文中详细介绍了相位抖动的提取和转化为单边带相位噪声的过程,以及相位噪声测量系统的硬件和软件实现。硬件主要包括信号的整形放大、电平转换以及重合检测。软件主要是基于LabVIEW的相位抖动提取和到相位噪声的转换。同时,利用这一系统对频率源的相位噪声进行测量,并将其测量结果和PN8010的进行比较和分析,找出其中的不足,然后进行适当的改进。
[Abstract]:Phase noise is an important technical index to measure the frequency standard source and modern electronic equipment. It is becoming more and more important in the study of the characteristics of the basic frequency source and the testing of the performance of the basic frequency source.Based on the periodic variation of phase between periodic signals, the phase noise measurement with high resolution is realized by using phase coincidence detection technique.The phase relationship between periodic signals is studied in depth, which provides a theoretical basis for phase coincidence detection of fuzzy regions.In the design of the coincidence detection circuit, because of the certain resolution of the phase coincidence detection circuit, the output of the coincidence pulse is realized when the phase difference of the two input signals is less than a certain value.This technique can realize the fast response time and high resolution phase noise measurement of a wide range of arbitrary frequency signals by using a single reference source, which is different from the traditional phase noise measurement system based on complex circuits.It not only saves the cost, but also improves the measuring accuracy.The measurement of phase noise is divided into the near end and the far end. The specific design is as follows: 1. In the design of the near end phase noise measurement system, the principle is to change the counting value in the gate by fluctuation.The phase jitter is extracted by counting the signals between the phase coincidence points without gaps and the envelope of the overlapped pulse clusters.Finally, the phase jitter is converted to single sideband phase noise. For the measurement of remote phase noise, a phase noise measurement method based on phase coincidence detection fuzzy region feature is proposed in this paper, which is a new measurement method.When the nominal frequency of the reference and measured signals is the same or multiple and with small deviations, the phase difference between the two signals varies monotonously, so these overlapped pulses are concentrated and present a fuzzy region with an envelope shape.The resolution of coincidence detection line is stable, so the fuzzy area of coincidence detection is relatively stable.At the same time, there is a slight change in the fuzzy region, which is caused by phase noise.Therefore, the phase jitter information caused by noise can be extracted by using coincidence detection fuzzy region.The Wiener Sinchin theorem is the basis of the algorithm for phase noise measurement. This theorem describes the process from phase jitter to phase noise, which has experienced autocorrelation and fast Fourier transform.In this paper, the process of phase jitter extraction and transformation into single sideband phase noise, and the hardware and software implementation of phase noise measurement system are introduced in detail.Hardware includes signal shaping and amplification, level conversion and coincidence detection.The software is mainly based on LabVIEW phase jitter extraction and phase noise conversion.At the same time, the system is used to measure the phase noise of the frequency source, and the results of the measurement are compared and analyzed with PN8010 to find out the shortcomings, and then make appropriate improvement.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM933.312

【共引文献】