查询词典 pulse amplitude modulation

modulation is the transmission of information to be loaded onto a high-frequency signal in the process.amplitude modulation using signal to control the rate of carrier,with its linear modulation signal changes,and maintain the same carrier frequency.in the amplitude modulation,in accordance with the strength of signals in the spectrum of different components,it is divided into ordinary am (amplitude modulation standard am),with inhibition of bilateral carrier am,the carrier single sideband suppression am.the main difference is the different methods and structure of the spectrum.

摘 要：调制是将要传送的信息装载到某一高频信号上去的过程。振幅调制是用调制信号去控制载波的幅度，使其随调制信号线性变化，而保持载波的频率不变。在幅度调制中，根据已调信号的频谱分量不同，分为普通调幅、抑制载波的双边带调幅、抑制载波的单边带调幅。它们的主要区别是产生的方法和频谱结构不同。

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。

In order to bring about the spatial depth resolution of the image data obtained, the method according to the invention comprises the following steps: an electromagnetic wave is beamed onto the surface of a photonic mixed element comprising at least one pixel, the pixel having at least two light-sensitive modulation light gates Gam and Gbm and associated accumulation gates Ga and Gb; modulation light gate voltages Uam and Ubm, which are configured as Uam=Uo Um and Ubm=Uo-Um, are applied to the modulation light gates Gam and Gbm; a direct voltage, whose magnitude is at least the same as that of the total of Uo and the amplitude of the modulation voltage Um, is applied to the accumulation gates Ga and Gb; the charge carriers produced in the space charge region of the modulation light gates Gam and Gbm by the incident electromagnetic wave are subjected, as a function of the polarity of the modulation light gate voltages Uam and Ubm, to the potential gradient of a drift field and drift to the corresponding accumulation gate Ga or Gb; and the charges qa and qb which have drifted to the accumulation gates Ga and Gb, respectively, are diverted.

为了使得采用这样一种方法获得的图象数据具有空间深度分辨率，按照本发明的方法包含下述步骤：使电磁波成束在至少包含一个象素的光混合元件的表面上，该象素至少具有两个光敏调制光门G am 和G bm 以及相关的累积门G a 和G b ；将调制光门电压U am 和U bm 施加到调制光门G a 和G b 上，而调制光门电压的构成是U am=U o U m，U bm=U o -U m；将直流电压施加到累积门G a 和G b 上，而直流电压的幅度至少与U o 和调制电压U am的幅度的总和相同；使由入射电磁波在调制光门G am 和G bm 的空间电荷区中产生的载流子经受漂移场的电位梯度，并漂移到相应的累积门G a 或G b ，而电磁波是调制光门电压U am和U bm的极性的函数；已经分别漂移到累积门G a 和G b 的电荷的方向反向。

These pulses include a Gaussian pulse, a hyperbolic secant pulse, a Lorentzian pulse, a Poisson spectrum pulse, a asymmetrical hyperbolic secant pulse, a rectangular pulse, a chirped Gaussian pulse and a chirped super-Gaussian pulse.

本论文基于上述提及的基本概念、分析方法和衍射积分理论，以描述超短脉冲光束的数学物理模型(包括超短脉冲高斯光束、超短脉冲贝塞耳—高斯光束、超短脉冲拉盖尔—高斯光束和超短啁啾脉冲光束等)为主要研究对象，研究超短脉冲光束在自由空间、色散介质和通过光阑的传输特性和位相奇点附近的光谱异常行为。

I used the homemade ECDL to measure the 2S-3D two photon transition spectrum of Helium , the advantages are that the expense of homemade ECDL is cheap and have good output power. At the same time, I used the electronic part can be got in the market to manufacture a pulse generator in the experiment, the pulse generator can control the output frequency, the pulse width, the relative phase and also can simultaneously control four sets of systems or instruments need the TTL pulse control. The advantage is that the cost of the pulse generator is cheap and the pulse generator is stable. To isolate the magnetic field I used the magnetic foil to helium cell. I also built a gas discharge system, the switch sequence of this system can be controlled by the pulse generator. Finally I built a detecting system can measure the helium energy state. It is cheap and can be combined with the comb laser system in my laboratory.

本实验是利用一台自制的外腔雷射系统来量测2S-3D的氦原子双光子跃迁，其优点在於自制的外腔雷射之费用非常便宜，也有不错的输出功率，同时在实验中我利用市售的电子零件制作了一台脉冲产生器，可控制输出的频率、脉冲宽度以及相对的相位，且可同时控制四套需要TTL脉冲控制的系统或仪器，优点除了便宜之外，也非常稳定；为了隔绝磁场，利用了磁场隔绝金属箔，我也在实验室中建立了一组气体放电系统，其系统可以用脉冲产生器来控制开关时序，最后，我建造了一个氦原子能阶的量测系统，而且费用低廉，可与本实验室的另外一门研究光梳雷射系统做结合。

I used the homemade ECDL to measure the 2S-3D two photon transition spectrum of Helium , the advantages are that the expense of homemade ECDL is cheap and have good output power. At the same time, I used the electronic part can be got in the market to manufacture a pulse generator in the experiment, the pulse generator can control the output frequency, the pulse width, the relative phase and also can simultaneously control four sets of systems or instruments need the TTL pulse control. The advantage is that the cost of the pulse generator is cheap and the pulse generator is stable. To isolate the magnetic field I used the magnetic foil to helium cell. I also built a gas discharge system, the switch sequence of this system can be controlled by the pulse generator. Finally I built a detecting system can measure the helium energy state.

本实验是利用一台自制的外腔雷射系统来量测2S-3D的氦原子双光子跃迁，其优点在於自制的外腔雷射之费用非常便宜，也有不错的输出功率，同时在实验中我利用市售的电子零件制作了一台脉冲产生器，可控制输出的频率、脉冲宽度以及相对的相位，且可同时控制四套需要TTL脉冲控制的系统或仪器，优点除了便宜之外，也非常稳定；为了隔绝磁场，利用了磁场隔绝金属箔，我也在实验室中建立了一组气体放电系统，其系统可以用脉冲产生器来控制开关时序，最后，我建造了一个氦原子能阶的量测系统，而且费用低廉，可与本实验室的另外一门研究光梳雷射系统做结合。

Switching Power Supply has three kinds of control circuits: Pulse Width Modulation, Pulse Frequency Modulation, Pulse Width and Frequency Modulation.

开关电源有三种控制方式：脉冲宽度调制、脉冲频率调制、脉冲宽度频率调制。

After the section of right side NXIIts in Budgerigar in the original sound wave\'s expanded time window, the higher amplitude pulse and the lower amplitude pulse exchanged alternately and also the higher amplitude is approximately as twice as the lower amplitude. The above outcomes show that NXIIts is most important in controlling the tone varieties and the numbers of the harmonic parts and the course of the vocal control maybe a process of alternative replacing.

NXlltS可能在控制其鸣声的音调变化以及影响其呜声的谐波数量上起到一定的作用，其控制区发声的过程很可能具有交替更换的特性。

Seven kinds of antijamming methods,such as time correlated choice and field-of-view shrinkage, inertial track,real-time memory criterion,amplitude discrimination, pulse-width discrimination, pulse-amplitude time sequence discrimination and pulse-width amplitude discrimination for Counter-Infrared-Interference-Missile with the cross-shaped detector array are given.

介绍了四元正交探测器以及红外干扰弹的工作原理，对四元正交探测器导引系统抗红外干扰的7种方法(即时间相关选择和视场收缩技术、惯性跟踪机制、实时记忆准则、幅值鉴别法、脉冲宽度鉴别法、脉冲幅值序列鉴别法和脉冲宽度幅值鉴别法)等进行了讨论。

A design and implementation method of the high speed modulation system, which adopted the new techniques of the FPGA and DAC based communication system,is presented in this paper. The effect of the key techniques of this system, such as the high speed digital signal processing for modulation, high speed based-band signal conversion, wide-band modulation, carrier suppression, high frequency and high precision system clock generation, is analyzed, and the solutions and performance analysis is also given. Finally, a high speed modulation system for space applications is implemented, can be used for high speed data transmission with QPSK, 8PSK, QAM or other kinds of digital modulation.

本论文依据正交调制原理，采用基于FPGA和DAC的设计技术，提出了一种高速、灵活的调制系统的设计方法，重点分析了系统组成的调制编码映射、基带脉冲信号转换、信号滤波、调制、系统时钟产生等关键技术环节的影响，解决了高速调制信号处理、高速数据转换、宽带调制、载波抑制、高频率高精度系统时钟的产生等关键技术问题，完成了一种适用于空间应用的高传输速率、多进制数字调制方式和调制体制灵活的数据传输调制系统的设计与实现，可在硬件设计不变的情况下，实现QPSK、8PSK和16QAM等多种调制方式的高速数据传输，QPSK调制速率达到500Mbps。

The production moved off-Broadway to New York City, where she won the Joseph E. Calloway award for her performance, and was profiled in American Theater Magazine as one of ten young theater artists to watch.

生产提出过百老汇的新的纽约市，在那里她赢得了约瑟夫calloway奖，她的表现，并于异型在美国的战区杂志之一， 10战区的青年艺术家观赏。

It's a risk tradeoff, and I believe that adding test support code usually wins.

这是一个风险的权衡，我相信添加测试代码通常会占上风。