查询词典 signal to noise ratio

The relationships of signal-to-noise ratio of sampled signal, analog filter before analog-to-digital converter and sampling rate have been discussed, the results of the discussion have instructiveness for the design of digital receivers.

该文讨论采样后信噪比与模数转换器前的模拟滤波器以及采样率之间的关系，所得结论对数字接收系统设计有指导意义。

It contributes to the noise figure of the EDFA which causes loss of signal-to-noise ratio.

放大的自发发射可以对引起信噪比损耗的EDFA噪声指数产生影响。

The loss of signal-to-noise ratio was used in comparing the noise performance of holograms before and after fixing.

探讨了双色存储全息图的图像保真度，采用信噪比损失描述双色固定过程对全息图像的像质影响。

As the mine accidents happen frequently in recent years, the detecting technology for microseism becomes much more important. However, there is no advanced microseism detecting system at home. It's pretty important for microseisms denoising and Reversion. A wavelet denoising method is presented here to process microseism signal, and the microseism record can get high signal to noise ratio. Meanwhile based on the software of LabVIEW, s design of real-time detecting system for microseism based on virtual instrument is presented. The advantage of the virtual instrument was sufficiently exerted to achieve the real-time detecting and analyzing of the microseism.

以往基于DSP或其他单片机的微震系统，其资源的有限性很难达到理想的采集效果，同时也难以完成先进算法的实现，而对微震信号的去噪与还原在监测系统中起着很重要的作用；在深入分析小波变换的信号去噪方法基础上，对微震信号进行了处理，得到高信噪比的微震记录，实现了对噪声的有效抑止；同时在LabVIEW平台软件设计的基础上，实现了一种基于虚拟仪器微震实时检测的设计方案，充分发挥了虚拟仪器的优势，结果表明基于LabVIEW的微震系统能很好地完成实时监测及其分析。

The results obtained from three different methods—the conventional numerical differentiation, the discrete wavelet transform method and the proposed continuous wavelet transform method were compared, it was demonstrated that the results are similar for signals without noise, but the signal-to-noise ratio of the result obtained by the CWT method is improved greatly comparing with the former two methods for noisy signals.

通过数值微分法、离散小波变换法及连续小波变换法对模拟信号的求导结果表明：对于无噪音的信号，三种方法的结果相似，而对于含有噪音的信号，连续小波变换法所得结果的信噪比明显高于前两种方法。

In order to improve the signal-to-noise ratio of the pulsar signal, a wavelet denoising algorithm based on fuzzy threshold is put forward.

为了提高脉冲星辐射脉冲信号的信噪比，提出了基于模糊阈值的小波降噪算法。

A phase-locked amplifier is used to improve the signal-to-noise ratio of photoelectricity signal, and a computer is utilized to incept the sampling sig...

用锁相放大器来提高光电信号的信噪比，信号被快速采样后由接口电路输入计算机，自动给出所测单模光纤的模场半径。

The unflatness of amplified spontaneous emission noise and its impacts imposed on the performance of the off-center narrow filter polarization-nulling method when monitoring the in-band optical signal-to-noise ratio of dense wavelength division multiplexing system are analyzed, and a modified method by introducing an unflat factor in the calculation of OSNR is proposed.

分析了累积自发辐射噪声的非平坦特性，在已有窄带离心偏振置零法测量波分复用系统中带内光信噪比的基础上，分析该方法在噪声非平坦条件下存在的问题，提出了在光信噪比的计算中引入修正因子。

To meet the needs, a novel low-noise fiber laser with compound cavity structure is designed. The stable single-mode operation is realized by using a transient self-written fiber grating, produced by the effect of saturable absorption within a section of unpumped erbium-doped fiber, as narrow band filter for mode selecting and linewidth squeezing. Through optical path modification, the spectral signal-to-noise ratio is better than 62 dB.

激光器采用复合腔结构，以掺铒光纤作为工作物质，通过在未被抽运的掺铒光纤中形成的瞬态自写入光纤光栅的窄带滤波特性进行选模和压窄线宽，产生稳定的单频激光输出；经过光路改进，激光输出光谱信噪比优于62 dB；利用光电负反馈电路，弛豫振荡峰下降了约25 dB，低频段强度噪声也大为改善，有效地抑制了光源的强度噪声。

Starting from the output signal-to-noise ratio of vibration tables, the basic requirements of background noise of the foundation are determined, then the dynamic analysis of the foundation for tables and a laser vibrometer, and the static analysis of the foundation for the laser vibrometer are done with finite element method.

首先以振动台台面输出信噪比为出发点，确定了超低频标准振动台基础噪声的基本要求；然后采用有限元分析的数值方法，分别对振动台基础与激光测振仪基础作动力学分析，再对激光测振仪基础作静力学分析。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。