查询词典 signal to noise ratio

Due to the fact that the intercarrier spacing in OFDM is relatively small, OFDM transceivers are somewhat more sensitive to phase noise compared to single carrier transceivers. Thus this problem must be carefully considered in designing an OFDMbased system since an accurate prediction of the tolerable phase noise can allow designer to relax system specifications. According to spectrum theorem, two components of phase noise were analyzed: common phase error and intercarrier interference. On the basis of the analysis, the performance of OFDM was given for the case where phase noise has been added to the signal, and an optimal design criterion for OFDM parameters was proposed that allows to improve the phase noise error correcting capabilities in OFDM receiver.

由于采用子载波间相互正交的结构，OFDM系统对于由本地振荡器不稳定性所导致的相位噪声影响非常敏感，针对公共相位误差CPE和载波间干扰ICI两种影响表现形式不同的干扰项，从功率谱密度函数这一独特角度分析了相位噪声对OFDM系统性能的影响，提出了旨在提高接收机抵抗相位噪声能力的OFDM系统关键参数优化与设计准则，可在对所设计OFDM系统性能加以提高的同时，有效降低对接收机前端模拟振荡器件和相位噪声抑制单元的性能指标要求，从而降低接收机硬件实现成本。

The noise frequency modulation signal was particularly analyzed. The Fokker-Planck equation of noise frequency modulation was presented and the Motion-Group Fourier Transform was used by converting the partial differential equation into the variable coefficient homogenous linear differential equations. Then the solutions were given by using the peano-baker series. So the probability density function of noise frequency modulation in the filter was given. On the basis of the probability density function the stochastic resonance of noise frequency modulation signal is analyzed.

首先建立了噪声调频干扰信号通过脉冲压缩雷达中频滤波器后所满足的福克尔－普朗克方程，然后利用群移傅立叶变换（Motion-Group Fourier Transform，MGFT）将此偏微分方程化成了变系数齐次线性微分方程组，并利用Peano-Baker级数法给出了该方程组的解，最后得到了噪声调频干扰信号通过脉冲压缩雷达中频滤波器后的概率密度函数，在此基础上研究了噪声调频干扰信号造成的随机共振现象。

The information includes combustion, valve-open and valve-close information. But this signal also contains interfering noise, like exhaust noise and other noise eradiated from the other part of the diesel engine, and the frequency composition of useful signal and interfering noise are largely overlapped in the frequency band under 20 KHz.

但是提取的缸盖噪声信号中也含有柴油机工作时产生的排气噪声和机体其它部位辐射噪声等干扰信号，且干扰信号与有用信号的频率成分在20 kHz以下的频带内重叠在一起。

Increasing the input noise may increase the signal-to-noise ratio of the output response V(t within the element's parameter region indicating that the periodic components of V increase as the input noise increases. The relationsip between the variation of the SNR of the V curve and the noise is similar to the that of the resonance.

结果表明：在一定的条件下，增大输入噪声的值不仅不降低输出响应信噪比；反而迅速增加输出响应的信噪比，使输出响应中周期信号的分量反而加强，而且输出响应的信噪比对于输入噪声的变化具有&共振&形状的曲线。

However, this is mostly true for signals we receive directly, like noise sources, and not so much for signals from broadcast stations coming to us through skywave propagation. I aim the antenna for minimum noise pickup, which results in the best signal to noise ratio. In some situations it is quite possible to fully tune out a noise source such as a TV or computer monitor.

喜欢听干扰台的有福了，VOA和干扰台的信号不会是一个方向来的，把环对准VOA信号最强的方向，那么在另外方向的干扰信号就会衰减，VOA来的斗争指示你会听得更清），我更感兴趣的是最小噪声拾取，这会带来会好的信噪比，在一些情况下，很有可能将电视或电脑带来的噪声剔出出去。

The additive noise factor has relation with SOA"s linewidth enhancement factor and it is always larger than one, which means that interferometer"s output signal-to-noise is different under different working mode. Adopting feedback working mode we can obtain higher signal-to-noise ratio. The experimental results prove the correctness of theory analysis.

该附加噪声因子和SOA线宽增强因子相关且始终大于1，说明在考虑SOA的噪声时干涉仪在两种工作模式下输出信号的信噪比是不同的，采用返回式工作模式能获得更高的信噪比，实验结果和理论分析相吻合。

The objective parameters, including fundamental frequency, jitter, shimmer, fundamental frequency standard deviation, maximal frequency, minimal frequence, normalized noise energy, harmonic-to-noise ratio, signal-to-noise ratio and maximal phonatory time which were measured mainly on a sustained /a/ were recorded on an Dr.

客观检测采用Dr.speech for windows嗓音评估软件，在长元音／a：／上检测下列参数：基频、基频微扰、振幅微扰、基频标准差、最大基频、最小基频、声门噪声能量、谐噪比、信噪比和最大发声时间。

Firstly, it discusses the principle of adaptive interference chancellor, including broad band signal and narrow band signal; Secondly, it analysises one common algorithm used in adaptive interference chancellor, that is, LMS algorithm and its anamorphosis algorithm especially normalized LMS algorithm pointing out their relationship. After then, the paper talks about the structure and reality of canceling broad band noise in narrow band signal and narrow band noise in broad band signal and gives it's result simulation analyzing the factors affecting the power of the algorithm. In the last party, it gives the hardware design and assembly language software design using TMS32OC3 1, including the result of simulating.

首先，本文讨论了自适应干扰对消的原理，并对窄带信号和宽带信号两种进行了分别分析；然后本文对自适应干扰对消中常用的算法—LMS算法进行了分析，同时也讨论了LMS算法的变形算法，尤其是归一化LMS算法，并指出了这些算法的相同和不同之处；此后，本文讨论了窄带信号中的宽带干扰对消和宽带信号中的窄带干扰对消的结构及实现方法并给出了住址的结果，分析了影响干扰对消效果的因素；在论文的最后，给出了用TMS320C31实现窄带信号中的宽带干扰对消的硬件设计和汇编程序设计，以及汇编语言程序的结果，并就此结果与高级语言程序的结果作了比较。

It has proved that under the circumstance of low signal/noise rate, for either single LFM signal or multi-LFM signal, compared with traditional methods, this method can more effectively inhibit different kinds of Gaussian noise, avoid the influence of cross term and identify useful signal.

结果表明，在低信噪比情况下，无论是针对单分量LFM信号还是多分量LFM信号，该方法都可以比传统方法更有效地抑制各种高斯噪声，摆脱交叉项的影响，识别有用信号。

It is the relationship of the true signal to the noise signal, known as the signal-to-noise ratio, which is of most interest to the communication engineer.

这是关系的真实信号，噪声信号，为信号与噪声的比例，这是最感兴趣的通信工程师。

Through comparing with the results by simulation to study the effects of theprojectile"s final velocity, the angle of rotation and the ballistic trajectory"s migration withdifferent projectile"s rotating speeds, different target"s moving speeds and differentpenetration angles.

通过比较数值模拟的结果来研究不同弹头转速、目标速度、侵彻角对侵彻过程中弹头最终速度、翻转角度和弹道偏移的影响。

I love stationery and all the accoutrement of writing.

我爱文具以及所有的书写的工具装备。