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1.
微弱信号的提取在信号检测中占据十分重要的地位,文中研究了一种基于TS201芯片的微弱信号的检测平台设计,利用正弦信号的特性,进行多重自相关运算,有效的提高信噪比,提取淹没于噪声背景下的微弱信号。文中给出了具体的硬件结构设计和算法实验。实验结果表明,检测平台能有效的提取微弱信号。  相似文献   
2.
在国内阿仑方差(Allan Variance)通常用来表征原子频标的频率稳定度。在国外,通常运用哈达玛方差(Adamard Vatiance)测量铷原子频标长期频率稳定度。简要介绍了哈达玛方差在铷原子频标日频率稳定度测试中的具体应用,并对测量结果进行了分析。  相似文献   
3.
介绍了带液晶显示的多参数输出测试装置,该系统由89C52微处理器和12位A/D转换芯片AD574及12位D/A转换芯片AD7522实现,并带有RS—232通信接口和CAN总线,便于组成DCS或FCS系统。  相似文献   
4.
Detection resolution is crucial for improvement of the measurement precision in the device and instrument. Because of the limited resolution, a fuzzy area with the truth-value as its center is found during the detection. The finding for improving the measurement precision by the border of fuzzy area is first introduced. The higher resolution can be captured by the higher resolution stability which makes the different detection results of the inner and outer fuzzy area on the border reflected more sensitively between the measure and the reference quantity. The system resolution obtained only depends on the stability of measurement resolution, which is much better than the mea~surement resolution itself. Based on the finding, the measurement precision can be improved two or three orders of magnitude. The finding can be used in various kinds of high precision measurement.  相似文献   
5.
We analyze the phenomena of phase group synchronization between the different nominal frequency signals and propose a new theory of the equivalent comparison between them. The exact expression of the equivalent comparison is deduced. High resolution frequency measurement and phase comparison can be realized using this theory with the divider. For avoiding the frequency mixing, multiplication and synthesis, the system phase noise is improved and the higher resolution comparison and measurement are achieved between the different nominal frequencies by theory.  相似文献   
6.
李智奇  周渭  陈发喜  刘晨光 《中国物理 B》2010,19(9):90601-090601
A method for super high resolution comparison measurement is proposed in this paper with a comparison between the frequency standards of different nominal frequencies, which is based on phase coincidence detection of the two compared signals. It utilizes the regular phase shift characteristics between the signals. The resolution of the measurement approach can reach 10-13/s at 5 MHz, and the self-calibration resolution can achieve 10-14/s in the comparison between 10 MHz and 100 MHz, or even can reach 10-15/s in the comparison between 10 MHz and 190 MHz. This method implies significant progress in the development of the high precision frequency standard comparison technology.  相似文献   
7.
软件模拟ⅡC时序的通讯实现   总被引:1,自引:0,他引:1  
介绍了ⅡC总线的时序协议,并利用C语言对89S51单片机编程,软件模拟ⅡC总线的通讯协议和具有ⅡC接口的数字电位器X9241进行通讯,并把电位器应用在晶体振荡器的拐点查找中,得到电阻频率曲线,实现晶体拐点的查找,认为这种方法方便可靠,减少了硬件的开支,并且便于扩展使用。  相似文献   
8.
软件模拟IIC时序的通讯实现   总被引:1,自引:0,他引:1  
介绍了llC总线的时序协议,并利用C语言对89S51单片机编程,软件模拟IIC总线的通讯协议和具有IIC接口的数字电位器X9241进行通讯,并把电位器应用在晶体振荡器的拐点查找中,得到电阻频率曲线,实现晶体拐点的查找,认为这种方法方便可靠,减少了硬件的开支,并且便于扩展使用.  相似文献   
9.
Phase comparison method can enhance the measurement resolution to 10^-13/T in time domain. This method can also be used in distance measurement in the navigation and positioning. We propose a super high-resolution distance measurement based on linear phase comparison method. A high resolution scheme is put forward on the basis of the research of major factors concerning the phase comparison in the distance measurement. Conversion of a high-linearity phase difference to voltage and high-resolution voltage meter make it possible to obtain a very high phase measurement resolution. When the purpose is to measure distance, the phase noise of frequency source used in the measurement can be reduced partly. Thus this method is favourable for high resolution distance measurement. The precision of the distance measurement can reach 0.1c ps with c being the velocity of light in vacuum.  相似文献   
10.
在对两个周期性信号之间相位差变化规律和相应的新概念深入研究的基础上,结合常用的频率稳定度的测量方法,提出了一种新的频率稳定度的判定方法——基于李沙育图形的频率稳定度的快速检验方法。该方法可以用于各种原子频标和频率源的频率稳定度的测量与判定。  相似文献   
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