本文讨论了空气隙型光固定衰减器的回波损耗。
This paper discusses the return loss in air-space type fixed optical attenuator.
推导了雾、霾、云、大气的衰减随高度变化的规律，给出了云层激光回波特性的计算公式。
We get rules of the attenuation of fog, cloud, haze and atmosphere as the height changes, and give the calculation formula of the laser scattering character of cloud layer.
按照波动理论，在忽略衰减损耗的情况下，回波振幅（ ）。
Based upon wave theory and ignoring attenuation losses, the echo amplitude is.
目的探讨脑脊液衰减翻转恢复(FLAIR)与快速自旋回波(FSE)在颅脑的应用对比价值。
Objective To discuss the value of fluid attenuated inversion recovery (FLAIR) and fast spin echo (FSE) in MRI of the brain.
利用不同深度界面的回波频谱分析提取衰减系数剖面。
The attenuation is extracted by the spectrum of the layers at different depth.
在天气回波信号谱宽固定的情况下，通过改变天气回波信号的平均多普勒频率，分析了回归滤波器对它的衰减情况。
Fixing the spectrum width of the weather echo signals, we change theirs mean Doppler frequency and filter them using regression filter. After filtering, we analyze the attenuation of them.
本装置用超声脉冲回波与定标指数波形比较的方法测量超声衰减。
An instrument for measuring ultrasonic attenuation by means of comparing the ultrasonic pulse echo with a calibrated exponential decay wave-form is described.
介绍了模拟港口岸形、物标回波和其他助航物标回波的生成，雷达回波的干扰、遮挡和衰减，固定距标圈、电子方位线和活动距标圈的显隐与图像的有关裁剪算法等。
Also the details about the coast, target and other navigational subjects echo and the interference of echo and Ring, Ebl, Vrm of Radar and clipping algorithm etc.
采用时间增益补偿技术，补偿超声波在空气中的衰减，减少回波信号的起伏；由有源全波整流电路和微分电路等组成峰值时间检测电路，可正确检测回波的峰值到达时间。
The peak time detecting circuit which is composed of full-wave rectification circuit and differential circuit can detect the reach time of echo signal accurately.
采用时间增益补偿技术，补偿超声波在空气中的衰减，减少回波信号的起伏；由有源全波整流电路和微分电路等组成峰值时间检测电路，可正确检测回波的峰值到达时间。
The peak time detecting circuit which is composed of full-wave rectification circuit and differential circuit can detect the reach time of echo signal accurately.
应用推荐