查询词典 signal noise ratio

Under the condition of varying , the ratio between noise levels in local sensors, this dissertation derives the analytic expression of performance of the centralized OS-CFAR detection for and local signal-to-noise ratio in nonhomogenous background.

本文在局部传感器背景噪声功率水平间的相对比例系数变化情况下，推导出了集中式 OS-CFAR 检测在且局部观测信噪比条件下在非均匀杂波背景中检测性能的解析表达式。

Time courses of signal-to-noise ratio and contrast-to-noise ratio were analyzed.

分析信噪比和对比噪声比的时程。

The signal-phase-matching principle of three and multi sensors are proposed in this dissertation. By using these principles, the formulae of estimated spatial signal are derived. The physical meaning and the geometric interpretation of these principles are given. The performances of estimated signal are analyzed when the phase of expected signal and the amplitude of noise are fluctuant.

提出了三元阵及多元阵的信号相位匹配原理，推导了利用信号相位匹配原理的空间信号估计公式，给出了信号相位匹配原理的物理意义及几何解释，分析了信号相位和噪声幅度起伏对信号估计性能的影响。

Wavelet multi-resolution analysis is applied to decompose the signal into multiple-level and the wavelet coefficient modules of its high-frequency components are obtained. The wavelet coefficient modules of a broken signal can be extracted by software demising. The threshold of demising is decided by the difference between the wavelet coefficient modules of a broken signal and those of a noise. The wavelet coefficient modules of the broken signal were shown in different levels, then the faults can be detected and distinguished by the integrated features of the variant levels' wavelet coefficient modules.

利用小波多尺度分解技术，将信号进行多尺度的小波分解，得到不同尺度下的信号高频分量的小波系数模值，并根据奇变信号和噪声信号小波系数模值的差异，采用软阈值去噪法，对其高频分量小波系数进行去噪处理，获取不同尺度上突变信号的小波系数模值，实现对故障的检测，并可根据不同尺度上小波系数模值的对应关系，实现对多重并发故障的区分。

Two new functions based on the property of bubble wavelet are proposed. An approximate 2nd derivative of an analytical signal can be obtained by applying n times of the wavelet transform to the signal, the signal-to-noise ratio can be enhanced greatly.

根据小波的定义和墨西哥帽小波的一些特点提出了两种简单的窗口函数，利用它们对模拟高斯信号求2n阶近似导数的同时滤除了噪声，同时还可分离重叠峰，并讨论了尺度因子对变换结果的影响。

Combining the definition of CWT and the derivative property of convolution, we constructed a general method to calculate the approximate derivative of signal through CWT by using the first and second derivative of Gaussian function, Haar, and the first derivative of three-order-Spline function as wavelets. As compared with the other approaches of calculating derivative, which include the numerical differentiation, polynomial filters, Fourier transform, and the recently proposed DWT method, fast calculation and simple mathematical operation were remarkable advantages of CWT method. For the signal corrupted by severe noise (Signal-toNoise Ratio=5), the satisfactory results could also obtained via CWT method through appropriately adiusting the dilations.

在此基础上，(1)结合连续小波变换的特点和卷积的微分性质，提出了使用Gaussian函数的一阶和二阶导数，Haar和三次样条函数的一阶导数作为小波函数的连续小波变换计算信号近似导数的一般性方法，与其他导数计算方法(包括数字微分法，多项式滤波法，Fourier变换法和离散小波变换法)相比，本法简单便捷，计算速度快，对于噪声含量较高的信号(S/N为5)，只要适当调节尺度即可获得比较满意的结果。

Meanwhile, the high master frequency band signal acquisition channel makes full use of the cymoscope sensitivity and hardware dynamic range, has larger analog signals front-located gain, thereby reinforcing the signal-noise ratio of the high master frequency band signal, and bringing along benefits for the later stage high resolutions seismic data process.

同时由于高主频频带信号采集电路充分利用了检波器的灵敏度和硬件动态范围，具有较大的模拟信号前置增益，使得高主频频带信号的信噪比得到增强，为后期高分辨率地震资料处理带来了较大益处。

The Raman scatter signal of carbon tetrachloromethane with this capillary/fiber optical was acquired, From this spectra, the scatter signal intensity and the signal/noise ratio were enhanced about 20 fold.

：本文提出了一种用于拉曼光谱研究的新型毛细管/双光纤传感器，对传感器构型和特性进行了研究，并将其用于四氯化碳样品的研究。

Secondly, making use of the good time frequency characteristics of the wavelet analysis in the signal processing, the wavelet softthreshold filtering of the swing CO2 welding voltage signal under the arc discharge sense was carried out, showing the possibility of removing the peak current of the shortcircuit transition and improving the signal-to-noise ratio.

二是利用小波分析在信号处理上良好时域、频域局域性，对电弧传感方式下的摆动焊接电流进行了软阈值滤波，取得了良好的效果，消除了短路过渡所造成的峰值电流，提高了信噪比。

In this paper, the practical WDM multi-granularity traffic switching testing network is constructed and a novel method using eye diagram to monitor optical performance in the network is proposed. The method is demonstrated in the reconfigurable WDM multi-granularity traffic switching all-optical network and it results that it can realize supervision of optical signal to noise ratio, time jittering, channel power, extinction ratio and bit error rate of optical data stream of any wavelength channel in the network. The method is transparent to signal protocol and bit rates and is able to distinguish between different optical impairments.

摘要波分复用多粒度交换可重构全光网是当前光通信网发展的方向，该文构造了一种实际试验网，提出了一种&眼图法&对网中数字光信号进行全面监控的方法，并在自建WDM多粒度交换可重构全光网试验床上进行了演示，结果显示在网络重构等各种条件下均可对网中各波长通道数字信号的信噪比、定时抖动、功率、误码率等进行实时监测控制，该方法对光信号的协议和速率透明且能对各种光性能劣化进行鉴别。

"Yes, now you can give yourself airs," she said, you have got what you wanted.

"对了，您现在高兴了，"她说道，这是您所期待的。

Then the LORD said to me: Rebel Israel is inwardly more just than traitorous Judah.

上主于是对我说：＂失节的以色列比失信的犹大，更显得正义。