查询词典 modulation

In order to effectively reduce the effects of multi-access interference on the performance of optical code division multiple access communication systems with intensity modulation and direct detection,according to group information, a novel kind of multi-access interference cancellation scheme based on fiber Bragg gratingused with two dimensional address code MPC/OOC is presented.

摘要在强度调制、直接探测的光码分多址通信系统中，为了有效克服并发用户数之间的多址干扰，提高系统的通信性能，根据组信息，针对由光正交码和修正素数码构成的扩时/跳频地址码MPC/OOC，提出一种基于光纤布拉格光栅的多址干扰消除方案，并详细分析了采用这种多址干扰消除方案的光CDMA通信系统的性能。

Buck and Boost topology switching power conversion circuits as the core of this system, ultra low power MSP430F1222 microcontroller-based controller, microcontroller produced by the PWM pulse width modulation signals, respectively, two-way control switch voltage conversion circuit the turn-on and turn-off in order to achieve the above two kinds of topology switching power conversion circuit, and then to draw power from the flow of electrical energy has been filled into the rechargeable battery, and using microcontroller A / D input voltage implementation of the monitoring, according to the input voltage switching buck - circuit at a lower cost to achieve a highly efficient energy transfer, and the circuit is simple, the parameter to determine easy, self-low power consumption,to achieve full-featured.

本系统以Buck降压和Boost升压拓扑结构开关电源变换电路为核心，以超低功耗单片机MSP430F1222为主控器，由单片机产生PWM脉宽调制信号，分别控制两路电压变换电路中开关管的导通与关断从而实现以上两种拓扑结构开关电源变换电路，进而从一直流电源中吸取电能充入可充电电池，并利用单片机A/D对输入电压实施监测，根据输入电压切换升降压电路，以较低的成本实现了高效率的电能转移，并且电路简单、参数确定容易，自身功耗低，实现功能完整。

The maximum modulation for undistorted operation is that which varies the carrier amplitude between zero and twice its unmodulated value.

最大不失真调制是使载波幅度在O到两倍于未调制值的范围内变动。

To obtain the analytical solution of random response of the structure excited by uniform modulation model is very difficult in general.

均匀调制模型作用的结构随机响应很难给出解析解。

To eliminate common-mode voltage of cascaded multi-level inverter, three kinds of phase-difference SVM based on left and right bridge vectors are proposed firstly. From these three modulations, equivalent SPWM components are deduced, and the unipolarity and bipolarity of output waveforms are analyzed. 2π/3 PD-SVM (phase-difference space vector modulation) is testified be unipolar.

为消除级联型多电平逆变器的输出共模电压，首先提出了基于左、右桥臂矢量的三类相差空间矢量调制(space vector modulation，SVM)技术，数学推导出三类调制技术的等效正弦脉宽调制(sine pulse width modulation，SPWM)的调制波，并分析了其各自相电压输出波形的单、双极性，证明2π/3相差SVM必为单极性调制。

RFP will be taken as that delivered to the aerial and generally for the unmodulated condition; but in the case of systems in which the application of modulation

中，如使用调制引致有效载波功率增加(如载波及旁频带重新分配致使功率有任何改变除外)，则增加量无须计算在内。

The 8780A vector signal generator' wideband modulation is complemented with an unmodulated coherent carrier output for demodulation of test signals.

该8780a 矢量信号发生器'宽带调制，补充了一个 unmodulated 相干载波输出解调测试信号。

In our experiment, we use a low temperature heater to fuse the coupling section, the first polarization modulation waist point in the power transfer curve monitored with unpolarized 1312-nm laser light is taken as the stopping point in the coupler drawing process.

实验中，我们用一个低温热源加热耦合段，并采用圆偏振1 312 nm激光源作为监测源，在功率转换曲线上第一个偏振调制点处停止熔拉操作。

This paper studies measure techniques based on modulation , which do not need to unwrap .

本论文研究的基于调制度的光学三维测量方法则不需要去包裹。

A DC-to-DC converter includes a pulse width modulation circuit cooperating with at least one power switch for supplying power from a source to a load over a range between a lower limit and an upper limit to thereby control an output voltage for the load.

一种直流-直流转换器，包括一个与至少一个的电源开关协作，以在一个上限和下限的范围内由电源向负载供电，从而为负载控制输出电压的脉宽调制电路。

When this condition occurs, inbound replication with the source partner is stopped on the destination domain controller and event ID 2042 is logged in the Directory Services event log.

计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。

Instructions: click on the thumbnails to see a larger image, then use the left-right arrow keys to scroll through the slideshow.

使用说明：滑鼠点在小图上即可放大观赏。开启后键盘左右键可用来换照片。