查询词典 modulation capability

This article first described frequency changer's development process, proposed the PWM velocity modulation method's superiority, had pointed out the future PWM velocity modulation method's prospects for development, the spot will leave has studied the PWM velocity modulation method the significance.

本文首先描述了变频器的发展历程，提出了PWM调速方法的优势，指出了未来PWM调速方法的发展前景，点出了研究PWM调速方法的意义。

The modulation function can be calculated by Fourier transform, filtering and inverse Fourier transform. The value of modulation function in areas of local shadow and abrupt discontinuities is lower than that in other parts. So modulation is a useful threshold to determine the quality of carrier stripe.

针对这种情况，本论文提出了通过傅立叶变换得到变形条纹图像的调制度函数，设置调制度函数阈值判断条纹质量的优劣，低于阈值的部分认为是不连续、阴影或陡峭区域，使用模板覆盖。

In the thesis, the space vector modulation of MC can be synthesized by fictitious rectifier and fictitious inverter. Two space vector control strategies of MC, which combines output line voltage space vector modulation and input phase current space vector modulation, is adopted.

本文采用输出线电压空间矢量调制和输入相电流空间矢量调制相结合的双空间矢量调制策略，对虚拟整流器和虚拟逆变器的空间矢量分别进行了分析，然后将二者综合得到矩阵变换器的调制方法。

"There are two different modulation methods commonly used to do this: pulse-code modulation, which is widely used for transmission in common-carrier communications; and delta modulation, which is finding broad application in military communications."

完成这一转换通常有两种调制方法：脉码调制，这种调制方法广泛用于普通通信传输中；增量调制，这种调制方法在军事通信中使用较多。

Multicarrier modulation in data transmission is discussed in the fourth chapter. The performance of MCM and single tone modulation over twisted pairs is compared. Discrete multitone modulation is used in ADSL system. A new variable constellation TCM method is proposed, It can adapt to the subchannel capacity automatically. The simulation results prove that this method is quite effective.

第四章讨论了多载波调制技术在数据传输中的应用，针对市话信道的具体传输环境，比较了单载波调制与多载波调制的性能；针对ADSL传输的目标，采用离散多频音DMT技术，独立提出一种新的星座图变化的格状码方案VCTCM，能动态地适应不同子信道的传输能力，给出的计算机仿真结果表明该方案有较好的效果。

The composition voltage, the electric current double closed loop voltage-stabilized source, used the integrated phase shifting crystal thyratron module to do for the electrical energy transformation component, in detail has calculated the rectification main circuit main component parameter; In the pulse-duration modulation part, used the special-purpose integrated circuit to realize the frequency modulation to adjust the pressure, did take IGBT as the power transformation component, realized the output voltage frequency modulation to adjust the pressure, and has calculated the related parameter.

在调压稳压电压源设计中采用二阶工程设计法设计了电压和电流调节器，组成电压、电流双闭环稳压电源，采用集成移相晶闸管模块做为电能变换器件，详细计算了整流主电路主要器件的参数；在脉宽调制部分，采用专用集成电路实现了调频调压，以 IGBT 做为功率变换器件，实现了输出电压的调频调压，并计算了有关参数。

The amount of pulse width modulation pulse generators of the proposed modulation strategy is only the half of that of the traditional modulation strategy, which is of significant theoretical and practical value for the digital implementation of cascade multilevel converter.

该策略较传统的载波相移SPWM可以节省一半的脉宽调制(pulse width modulation，PWM)脉冲发生器，对级联型多电平逆变器的数字化实现有重要的理论和实用价值。

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。

The modulation that function of modulation of in-house AM, FM, PM, FSK makes the instrument can go to the lavatory is undee, and need not sole modulation source.

内部AM、FM、PM、FSK调制性能使仪器能够便利的调制波形，而无需零丁的调制源。

The paper investigates both block-type pilot linear minimum mean square error algorithm and IEEE802.16 OFDM channel estimation analysis. Simulation results confirm the block-type pilot structure is more suitable for IEEE802.16 system. An optimal pilot setting algorithm, based on space frequency domain, is explored and the pilot chart is presented. The proposed algorithm finds its application in MIMO-OFDM. Simulation results show the algorithm presents a good approximation to the perfect channel state information curve, with about 2dB difference in SNR. The simulation results also demonstrate the algorithm achieves fairly high stability in the environment of fast fading, performance of the proposed algorithm is better that of pilot training channel estimation.3. Taking into account the characteristics of IEEE802.16 OFDM system, OFDM system simulation platform is constructed in Matlab, exploiting simulink as a tool. OFDM modulation and demodulation simulation system are configured on LabVIEW platform. All the system signal processing is simulated, including defining system parameters, designing modulation model, and verifying all the proposed algorithms under different environments, such as white Gaussian noise, multi-path fading, with or without guard interval etc. Bit error performance is evaluated. The research provides valid theoretical basis for practical OFDM system performance evaluation.4. Taking advantage of software radio, the paper designs a hardware platform with both 256-IFFT/FFT and 512-IFFT/FFT OFDM schemes co-existing in one platform. You can predetermine one from the two schemes to carry out almost the same model function with different system performance and parameter setting.5. Referring to IEEE802.16 standard, the paper proposes a design method for generating signals and frames suitable for laboratory investigations implemented in laboratory environment.6. Based on 6701evm digital evaluation card, combined with analogy front-end, the paper designs a DSP software model to deal with baseband signal processing. An overall OFDM scheme, with modulation and demodulation function, is accomplished.

讨论分析了MIMO-OFDM中一种基于空频域的最优导频设置算法，给出了导频图案，通过仿真实验表明，该算法与理想的信道状态信息曲线非常接近，信噪比差距约在2dB左右，并且在快衰落条件下具有较好的稳定性，其性能要优于基于前导训练的信道估计方法。3、根据IEEE802.16OFDM系统特点，论文分别在Matlab中应用Simulink工具构建OFDM系统仿真平台、在LabVIEW平台上实现了OFDM调制解调仿真系统，模拟了整个系统的信号流程，进行了OFDM仿真系统参数的选择和调制模块的仿真设计、论证各算法性能，并根据各种不同的条件：例如高斯噪声、多径衰落、有无保护间隔等，对系统的误码特性进行了评估，为正确评价实际OFDM系统的性能提供了有效的理论依据。4、论文以软件无线电思想作为指导，提出了以256点IFFT／FFT为核心和以512点IFFT／FFT为核心的两种OFDM算法模式并存于同一个硬件平台、且可预选的方案，它们在参数选取和性能指标上有所差异，均实现了相似的模块和功能。5、论文参考IEEE 802.16无线网络标准的参数设置，针对本设计系统的应用环境和系统硬件的性能速率，提出了一种应用于实验室环境的信号结构、帧格式等参数设计。6、论文基于TI公司的6701evm数字评估板卡，结合模拟前端搭建数字中频平台，设计了基带处理的DSP软件模块并进行系统调试，基本实现了一套完整的OFDM调制解调方案。

And he is one of the few scouts who are occasionally sent out to have dealings with other peoples.

而他也是少数的几位偶尔会被派出去和外界人打交道的巡逻人员之一。

The sons of Hebron: Korah, Tappuah, Rekem and Shema.

希伯仑的儿子是可拉，他普亚，利肯，示玛。