查询词典 difference frequency

Variation laws of electron movement with emergence angle and microwave electromagnetic parameters are also derived. The emergence angle of electron has significant effect on the movement of electron, and there is an emergence angle in which the electron has the maximum trajectory length and impact energy, Impact energy will increase and return time will reduce as increasing the amplitude of electric field, and both parameter would oscillate with the phase of electric field, which can essentially explain that multipactoring electron number oscillates in twice the frequency with the increase of microwave frequency, electron trajectory will change from parabolic-like movement to complex oscillation.

研究发现：电子出射角度对其运动状态有显著影响，电子存在运动轨迹最大的某一出射角度，该角度下电子拥有最大的撞击能量；微波电场幅值的增加将使电子撞击能量增加，返回时间减小，微波电场相位的变化使电子的撞击能量和返回时间呈周期振荡，这从本质上解释了电子数量在二次电子倍增过程中以微波频率两倍周期振荡的原因；随着微波频率的增加电子将由简单的类抛物线运动转变为复杂的振荡运动。

In addition, the mode frequency would change with the variety of wind speed, while the angle of incidence had great effect on the frequency.

大桥振动频率会随着风速的增加而变化，而有效攻角对频率的变化起着重要作用。

The angular distribution of the bistaticscattering coefficient of HH polarization were obtained by numerical implementation. Influences of the permittivity and the mean layer thickness of intermediate medium, friction velocity and the frequency of the incident wave on the bistatic scattering coefficient were discussed. The basic characteristics, the zonal characteristics and the characteristics with varying of frequency of the scattering coefficient from stratified sea surface were obtained. The numerical results show that the scattering coefficient has approximate "quantization" characteristics.

通过数值计算得到了HH 极化双站散射系数随散射角的变化曲线，讨论了中间介质介电常数和厚度、摩擦风速和入射波频率对双站散射系数的影响，得到改进的一维分形分层海面散射系数的基本特征、分区特征和随频率变化的特征，结果表明散射系数近似具有"量子化"特征。

The angular distribution of the scattering coefficient of the HH polarization is obtained by numerical implementation, the influence of the fractal dimension, the special fundamental frequency, the scale interval, the permittivity of substrate medium, the permittivity and the mean layer thickness of intermediate medium, the root mean square of rough surface, and the frequency of the incident wave on the bistaticscattering coefficient is discussed.

通过数值计算得到了HH极化下双站散射系数随散射角的变化曲线，讨论了分维、空间基频、标度区间、底层介质介电常数、中间介质介电常数和厚度、粗糙面高度起伏均方根及入射波频率对双站散射系数的影响，得到了平面波入射一维带限Weierstrass分形分层介质粗糙面散射系数的分形特征、基本特征、分区特征和随频率变化的特征。

A new approach to eliminate the ranges dependence based on angular frequency shifting in space domain was presented, in which, the nonhomogeneity of clutter is removed and the blind area of target detection is reduced due to the fact that the clutter of all the compensated range cells in every channel is moved to the place of the clutter of the desired cell by the different angular frequency shifts being added into spatial data along all Doppler channels for every compensating range cell.

第七章针对非正侧视相控阵机载雷达，由于杂波在距离上呈现出严重的非均匀性，尤其是在近程这种依赖距离的杂波谱呈现的非均匀现象更为严重，使得用于计算自适应权的协方差矩阵不可能直接由距离单元数据统计平均来估计得到，否则STAP处理及其降维技术难以获得理想的杂波抑制性能和目标检测性能，甚至恶化。

The angular frequency of the disturbing force called the impressed frequency .

扰动力的角频率称为外加频率。

The consistency of the results from the present method and the scatter center model method are derived from the stationary phase method in high frequency region, whereas the present method is general and suitable for the analysis of angular glint in the entire frequency band.

利用驻相法说明所提方法和散射中心建模方法在高频区的结果是一致的，而所提方法适合在全频带上分析目标角闪烁。更具一般性。

Based MUSIC method, a new approach for estimating instantaneous frequency of linearity frequency modulating signals and simulations are carried out. The results prove this approach has higher precision and better antinoise.

基于MUSIC方法原理，本文提出了一种估计线性调频信号瞬时频率的新方法，并进行了详细仿真，指出该方法具有较高的精度与较好的抗噪性。

The results show that injection locking synchronization is realized when injection rate is large enough. In the injection locking regime, similarity index is larger for external modulation than that for direct modulation. If injection rate keeps unchanged, synchronization is little affected by modulation index, but it is affected by modulation frequency. Since outputs of the master laser are antiphase for direct modulation and external modulation, the fluctuations of similarity index with modulation frequency for the two lasers are contrary.

研究结果表明：当注入强度足够大时，系统实现注入锁定同步，外部调制的相似指数大于内部调制；注入强度恒定时，同步品质几乎不受调制指数的影响，而受调制频率的影响；由于内部、外部调制引起主激光器的输出反相，两种调制方式下同步品质随调制频率的变化趋势也相反。

The receptance characteristics of track system has been predicted with the three dimensional track for high frequency vibration, with this model, the structure parameters of track system affect onreceptance have been discussed. The results show that the stiffness of ballast, sleeper mass, and stiffness of railpad are the main factors affecting on resonance and antiresonance under second resonance frequency.

利用轨道系统高频振动模型预测了各种参数对轨道系统导纳特性的影响，结果表明：道床刚度、轨枕质量和轨枕垫刚度是影响轨道系统第二阶共振频率以下共振和反共振的主要因素，随道床刚度增加，或轨枕质量减小，或轨枕垫刚度增加，第一、二阶共振和第一阶反共振频率增加，道床阻尼、轨枕垫阻尼主要影响第一、二阶共振和第一阶反共振振幅，阻尼越大，共振峰值和反共振谷值越平缓。

"The operators will suffer a temporary decrease in the number of consumers and short message services as people may not like having to provide their ID cards for a phone number," Xu Junqi, vice-dean with the Policy-Making Institute of the Telecommunications Research Centre under MII, said yesterday.

信息产业部下属的通信决策研究院副主任徐俊其昨天说：&实行手机实名制后，人们可能不太情愿用身份证注册手机号，所以通信运营商会暂时面临用户减少和短信用户减少的问题。&

I don't believe in make-believe!

我不相信这些虚构的故事。