多普勒效应

• However , to achieve this objective , various technical challenges must be overcome . for example , the deployment of broad - band wireless access systems would require a transmission technique which can mitigate the detrimental effects of frequency selective fading
  为达到这一目的，有一些技术问题必须得到良好的解决，比方说在宽带通信模式下由于延迟扩展造成的频率选择性扩展和由多普勒效应产生的信道时域衰落。
• A mathematic model of reactor , steam generator , pressurizer is developed based on characteristic of pwr coolant system . for reactor , the point reactor kinetics equation with six - group delayed neutrons is used and influence of coolant ' s and fuel ' s temperature is considered , conduction model of one dimension and single - channel model is used in thermal and hydraulic calculation , third - order hermite polynomial is used to solve the point reactor kinetics equation
  对于反应堆，在物理计算中采用了带有六组缓发中子的点堆方程，同时考虑了多普勒效应及冷却剂温度效应对反应性的影响；在热工水力计算中采用了一维的热传导模型与单通道模型；在求解点堆方程中采用了hermite插值的方法，克服了点堆方程的刚性问题。
• For power control of listening users , forward power control method are introduced based on full , multichannel , filtered report , and collision method etc . the full report method has redundancy report information , and its real - time performance is bad , multichannel report is introduced to improve the real - time performance , and filtered report is introduced to eliminate the redundancy information , finally the collision method introduced can not only get higher real - time performance but also diminish the redundancy information ; 2 . in order to meet the requirements of making the dynamic simulation of trunking group system , the ms ’ s random move equation is brought forward , the simulation of ms ’ s distribution is done and the integrated channel model are presented ; 3 . the smart predicative model of power control is introduced to overcome the delay and track the change of the complicated network , with this model , the power control ‘ s performance is greatly improved
  全汇报方法存在冗余的汇报信息,而且实时性较差,为了改善实时性提出了多信道的汇报方式,为了改善冗余汇报而提出了筛选法,最后介绍的碰撞法在减少冗余信息的同时又提高了实时性;二、为了集群功率控制动态仿真的需要,提出了移动台的随机运动方程,进行了有关移动台的分布仿真,建立了综合的信道模型;三、希望克服延时和跟踪复杂网络环境变化,提出了功率控制的智能预测模型,通过智能预测模型可以改善功率控制的性能,着重介绍了采用神经网络的方法实现智能预测的通用模型,从而跟踪复杂多变的无线环境,诸如慢衰落及快衰落(包括多径衰落、多普勒效应所引起的衰落)等网络特征,达到预测功率需求;四、采用二级正交码和智能天线(空分多址)的方法进行组内用户的识别,改进功率控制效果;五、话权用户的前向和反向功率控制方法;六、对引入gota的cdma系统提出了复合容量表示方法,并作容量分析,探讨有关gota系统的qos问题。
• Laser doppler velocimeter ( ldv ) is a precise instrument based on the theory of laser doppler effect with no - touch measurement capability , quick responsibility , high precision , wide measurement range , multiple dimension measurement and direction judgement ability . ldv is applied extensively in the field of science research & education and industrial measurement . in this thesis , we researched on the high - precise signal processing in ldv
  激光多普勒测速仪( ldv )是根据激光多普勒效应研制而成的一种精密测速仪器,具有非接触测量、动态响应快、分析精度高、测量范围宽、可测多维速度和判别速度方向等优点,被广泛应用于科研教育领域和工业测量领域。
• Doppler radar is wide used , which utilizes the doppler shift between the target and radar to get the target information and process it . doppler radar has high performance on differentiating velocity , and it can efficiently solve the interference of the ground clutter to get the target echo from bad environment
  多普勒雷达是一种广泛采用的全相参体制的雷达,它利用目标与雷达之间相对运动而产生的多普勒效应进行目标信息提取和处理,具有较高的速度分辨率,可以有效地抑制杂波,能在较强的杂波背景中分辨出动目标回波。
• Secondly , based on the analysis and simulations of the doppler time - shift for chirp - subpulse stepped frequency signal , this dissertation analyses the velocity compensation method for moving targets in chirp - subpulse stepped frequency signal , and presents a method for compensation of targets ’ velocity base on the least burst error rule
  其次,本文对chirp子脉冲频率步进信号的多普勒效应进行了分析和仿真,在此基础上,分析了对其进行运动补偿的思路,提出了采用最小脉组误差准则进行运动补偿的方法。
• Being wireless channel , the channel of cdma system is very terrible medial of the nature , hi the course of transferring information , there are several disadvantages as time - selective fading , frequency - selective fading , near - far effect , multiple access interference , white gaussian noise and so on , which affect the reliability of cdma system and lower the capacity of cdma system
  然而cdma移动通信系统的信道为无线信道，它是自然界中的一种较为恶劣的通信介质。在信息的传输过程中，存在着多址干扰、高斯噪声、多径效应、远近效应及多普勒效应等诸多不利因素。这些不利因素极大地影响了cdma移动通系统的传输可靠性，限制了系统容量。
• To work out a mathematical relationship of the “ dopplereffect ” ， relating the pitch to the relative motion of source andobserver ， the austrian scientist christian johann doppler placedtrumpeters on a railroad flat car and musicians with a sense ofabsolute pitch near the tracks . a locomotive engine pulled theflat car back and forth at different speeds for two days . themusicians on the ground “ recorded ” the trumpet notes as the trainapproached and as it receded
  为了计算出“多普勒效应”的一个数学关系，即音调和运动中的声源和观察者之间的相对关系，奥地利科学家克里斯蒂?约翰?多普勒让几位吹号人坐在一节平板火车上，让几个对音调特别敏感的音乐家坐在铁轨附近。
• As a new velocity sensor , fvisar has the merit of compact structure , short coherence length , easy to adjustment light path , any fringe constant and so on . the principle of fvisar analyzed from two different theories ( traditional coherent theory and doppler frequency shift theory ) lead to the same velocity equation which is the solid theory foundation of the fvisar design
  第二章分别从经典的光干涉理论和多普勒效应两方面对fvisar的工作原理作了详尽的理论分析,两者得出了相同的速度计算公式,从而为全光纤速度传感器的设计打下坚实的理论基础。
• The paper , which is based on the " research and development of the speed - up train ' s manipulation of optimization and train simulator " project , concerns the sound system in the train simulator . in the paper , the sound system includes two parts contents : firstly , improving the sound effect of the sound simulation system in the train simulator and enhancing 3d sound effect , such as sense of distance , sense of orientation , doppler effect etc , to make the sound of training environment more verisimilar ; secondly , realization of the speech communication in network between teacher and student in the train simulator
  本文是以铁道部科技发展项目“提速列车优化操纵与机车仿真器研究开发”为依托，对机车仿真器的声音系统进行研究：第一，对机车仿真器中声音仿真系统的音效进行改进，增加3d音效，如声音的距离感、方位感、多普勒效应等，使得训练环境音响更加逼真；第二，实现机车仿真器中教员与学员间的语音网络通讯。