The disadvantage of FSO over fiber is that laser power attenuation through the atmosphere is variable and difficult to predict, for it is weather dependent. 由于信道和天气相关,因此,在大气中光功率的损耗是不确定的,并且难以预测。
Another is a power function equation for the dynamic attenuation of flux, which shows the real varying process of flux with time and fits the experimental data better than the existed linear one. 后者是一个幂函数模型,比原有的线性模型更贴近渗透通量随时间变化的实际过程。
Power Attenuation of Plasma Antenna Excited by Surface Wave 表面波等离子体天线的能量衰减系数研究
The hazard of higher harmonic in electric power system and its attenuation 电力系统高次谐波的危害及抑制方法
Because the dielectric constant of water is greater than others, the attenuation of microwave through the waver content material is caused by water, measuring the power of the microwave after attenuation, the water percentage is gained, This is the theory of microwave attenuation moisture measurement. 由于水的介电常数比其他物质大很多,经过含水物料后的微波能量衰减主要由水分引起,通过测量衰减后的微波能量可以测量出物料的含水率,这是微波衰减法测湿的原理。
By solving the coupled power equations of two-mode waveguide, the relations of power attenuation and conversion properties of guided modes to input and output powers from the optical waveguide have been derived. 本文在求解双模功率耦合方程的基础上,推得了导模的功率衰减和转换特性与光波导输入和输出功率的关系式。
Fibre-optical Monitoring Technology with a Little Power Attenuation for the Online Temperature in Medium-high-voltage System 中高压系统温度光纤在线监测低功耗设计技术
Furthermore, the formulae of transmitted power, loss power, attenuation constant and equivalent impedance for TM and TE modes are deduced. 此外,推导出波导TM、TE模的传输功率、损耗功率、衰减常数、等效阻抗等特征参数的边界元公式。
The simulated power indices of en-ergy spectra and attenuation lengths in air are in agreement with the experimental data. 模拟计算给出的能谱指数和衰减长度与实验结果相符;
These field distributions are necessary for investigating the power capacities, calculating the attenuation constants, considering the energy coupling, and designing related active devices. 基本上是准确的,在这个尺寸比稍大些时也可作为参考。这些场分布对于了解传输线的功率容量,计算衰减常数,考虑功率耦合,设计有关的有源器件等都是必不可少的。
In low field range, the change of current with time can be simulated by attenuation of power index, and the attenuation coefficient intends to decline with the increase of the applied electric field. 在弱场下,电流随时间的变化可用幂指数的衰减来模拟,而且衰减系数随场强的增加有减小的趋势。
Numerical Calculation of S-C Electromagnetic Forces of Power Transformer with Attenuation 考虑衰减时变压器短路电磁力的数值计算
In the glass waveguide formed by ion exchange, holographic grating and glass prism were used as input and output couplers respectively, input and output powers from the optical waveguide were measured, and the power attenuation and conversion coefficients of guided modes have been determined. 在离子交换玻璃波导上,将全息光栅和玻璃棱镜分别用作输入和输出耦合器,测得了光波导的输入和输出功率,并确定导模的功率衰减系数和功率转换系数。
In the minus power function formula of ground vibration attenuation, equivalent coefficient k is associated with the heavy tamping energy and the condition of soil mass in the site; 地面振动随距离的负指数幂衰减公式中当量系数k值的大小与强夯夯击能和场地介质条件有关;
Based on the Fourier transform analysis of saw tooth signal frequency modulation, the concept of power spectrum spread attenuation factor in the case of barrage jamming is presented. 首先通过对锯齿波调频的傅里叶变换,提出了阻塞式干扰下功率谱扩展衰减因子概念;
Laser communications has many advantages such as high-data-rate, high-bandwidth, significant cost savings, small size, light weight, low power attenuation. 其具有传输速率高、可用频带宽、安全可靠性高、保密性强、终端设备体积小、重量轻、功耗低等优点。
Measurement of the power attenuation and conversion properties of guided modes 导模的功率衰减和转换特性的测量
Based on a certain pattern, this paper discusses the design guide line and concrete implementation scheme of a general-purpose PD missile header target simulator. Some pivotal techniques are emphasized, including broad-band receiving, SSB modulation of video-frequency echo, and high precision power attenuation. 叙述了基于某型PD导引头的通用目标模拟器的设计思路和具体实现方案,着重介绍了系统中所应用的宽带接收、视频回波的单边带调制和高精度功率衰减技术。
And the author on the first time brings forward the method of determine the angle of zero power in Direct Current Attenuation Method by means of curve imitation, which provides a novel method to solve this difficult problem. 首次提出了在直接负载法中利用曲线拟合的处理方法来确定零功角状态的问题,为解决此难点问题提供了一种新的方法。
Robust nonlinear control for power system excitation via disturbance attenuation 通过干扰抑制实现电力系统励磁鲁棒非线性控制
Study on the Establishment Power Curve Model of Antibody Attenuation Trend of the Measles Live Vaccine and Prospect for the Antibody Permanence of the Vaccine by Model 麻疹减毒活疫苗抗体衰减趋势的幂曲线模型拟合及抗体持久性预测研究
However, the power line was originally designed for the transmission of electrical energy, when used for data communication, the Low-voltage power line channel represents high attenuation, high noise and time-varying characteristic, resulting in data communication distance is limited, the reliability is not high. 然而,电力线最初的设计是用于传输电能的,当用于数据通信时,信号衰减大、干扰强,且具有较强的时变性,导致通信距离有限,可靠性不高。
When laser beam propagates through the atmosphere as the information carrier, it will be influenced by power attenuation and turbulence effects, and the performance of FSO systems will be degraded. 当作为信息载体的激光束在大气中传输时,会受到大气衰减和湍流效应等一系列影响,导致通信系统性能降低。
Some physical properties of atmosphere and atmospheric phenomena such as clouds and fogs were introduced. The problem of power attenuation caused by atmospheric absorption and scattering was analyzed. 介绍了大气的各种物理性质和云、雾等大气现象,分析了大气吸收和散射引起的衰减效应。
Considering energy for transmitting data and neighbor nodes 'residual energy, the new weight function and three power attenuation models such as stepwise attenuation model. γ n order attenuation model and linear attenuation model are introduced. 该算法综合考虑网络中节点间数据传输的能耗和邻居节点的剩余能量,引入新的权值函数和阶梯衰减模型、γn阶衰减模型和线性衰减模型三种功率衰减模型。
Due to propagation obstacles in such environment, the received signal usually suffers heavy power attenuation multipath effects and cross-correlation interference, which is a big challenge for the research on technology of weak GNSS signal receiving. 因传播路径中障碍物的遮挡,功率衰减、多径及互相关干扰等问题均成为微弱GNSS信号接收技术研究的挑战。
Using the power function to fit capacity attenuation curve and fitting parameters by the experimental data, the ultimate expression is obtained at last. Then it is proved to be reasonable and correct by the experimental data. 运用幂函数对容量衰减曲线进行拟合并通过实验数据进行参数的修正,得到电池容量衰减的最终表达式,然后利用电池充放电循环试验,验证电池容量衰减率表达式的正确性和合理性。
Compared with traditional PTC ceramic materials, PTC metal film thermistor possesses many advantages such as extreme low resistance, fast heat up, high safety factor, long working life, no noise, little power attenuation, high mechanical strength, high flexibility and good sealing properties. 金属膜PTC热敏材料与传统的陶瓷PTC材料相比,具有阻值极低、加热快速、安全系数高、工作寿命长、无噪音、功率衰减小、机械强度高、密封性好及灵活性强等优点。
The sea/ air interface is fluctuant and influenced by wind speed or other acting force inducing inclination. Laser beams through the interface propagation direction becomes more complex bring on spreading and wandering, thus causing the whole object power attenuation. 激光通过大气/海水界面时,由于风速及其它外力的作用,粗糙海面发生倾斜,激光通过粗糙海面时的传播方向变得更加复杂化,激光产生扩散和漂移,从而引起整个光斑能量的衰减。
The results show that: in a plant on the ground conditions, power density attenuation more obvious, while the temperature, humidity, no significant effect on the power density; glass on the electromagnetic radiation shielding capability is weak. 研究结果表明:在有植物的地面条件中,功率密度的衰减量比较明显,而温度、湿度对功率密度的影响不明显;玻璃对电磁辐射的屏蔽能力较弱。