微弱正弦信号检测新方法

本文研究了一种新的检测微弱正弦信号的新方法。利用正弦信号的特殊特性．引人参考信号．与被测信号进行多重互相关运算,成功检测淹没于噪声中的正弦信号。分别讨论了白噪声、谐波、直流电平干扰情况下的检测效果,绘出了具体的仿真结果。实验结果表明．本文算法能提取出极低信噪比的微弱信号,对谐波和直流电平不敏感,同时本文的算法不会破坏微弱正弦信号的初相位信息．因此。工程适用范围更广。     

一种高精度的电力系统频率估计算法

该文研究了一种基于多重相关原理的电力系统频率估计算法,利用正弦信号的相关特性,对信号进行多重相关运算．极大地提高了信号的信噪比,提高了测量精度。分别讨论了信号的信噪比,采样点数,MD的量化位数对测量结果的影响,并给出了具体的仿真结果,并与传统的疗法进行了比较。实验表明这种方法能有效地对信噪比很低的信号的频率进行估计,在低信噪比下,精度比传统的方法要高1-2个数量级,而且算法简单,物理意义明确,精度却可以满足工程的要求。     

一种基于均匀量化移相的精密时间间隔测量技术

随着导航定位、空间技术的发展,对特高分辨率的时间测量以及高频率信号测量提出了更高要求。基于信号传输稳定的自然现象,文中提出了一种新的测量时间间隔的方法,利用信号的时相关系,对时钟信号进行均匀量化移相,等效的提高的时钟脉冲的频率,精度可以大大提高,对器件的要求可以降低,实现起来也非常简单。     

A Super High Resolution Distance Measurement Method Based on Phase Comparison

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.