查询词典 pulse-code modulation

We present the linear extrapolation which predicts the required optimum normalized fiber lengths for the optimum pulse compression experiments. Two of the most important nonlinear processes occurring in optical fiber are sefl phase modulation and stimulated Raman scattering .

我们从理论上首次分析了波破裂现象对光纤-光栅对激光脉冲压缩的影响，对以往的经验公式予以修正，给出了最佳脉冲压缩实验所要求的光纤长度的经验公式，以方便激光脉冲压缩实验中对光纤长度的选择要求。

The task of this project is to design a hardware platform for radar video simulation and calculate the pulse-compression video signal of linear frequency modulation radar system.

在深入分析了线性调频脉冲压缩信号产生过程和特性的基础上，结合16位定点DSP——TMS320C5402的硬件结构和指令系统的特点，编写了定点DSP程序，并对程序的计算量和计算结果进行了分析，表明算法的速度和精度都可以满足系统的要求。

In this study, two-tone stimulus paradigm with inter-pulse interval of 50 ms was used and two kinds of maskers, static frequency masker and dynamic frequency masker (up-sweep frequency modulation sound), were delivered to the animal before the probe under free field stimulation conditions.

自由声场刺激条件下，采用一定间隔的双声刺激模式(前一个声音为掩蔽声，后一个声音为探测声)，记录昆明小鼠下丘(inferior colliculus， IC)神经元的声反应。

After rigorously mathematical deduction, some valuable conclusions are drawn: at the multiple times of symbol period, discrete peaks of the PACA function appear with 3 peaks in group, which includes a larger peak located in the middle and the other smaller two located symmetricly beside the larger one. The distance between small peaks is modulation offset of pulse position PPM.

经过严格数学推导，指出了TH-UWB信号的PACA函数不但在字符周期整数倍处出现离散峰值，而且按三个峰值(一大峰值左右对称出现小峰值)成对出现，大峰和小峰的间隔就是PPM调制时间偏移。

Considering the ionospheric refractive index in geomagnetic field, the radiowave polarization plane rotation has been calculated. For linear frequency modulation pulse signal, the expression of Doppler shift error due to ionospheric dispersion characteristics is derived.

本文还计算了考虑地磁场时电离层双折射指数特性引起的电波极化面旋转角，推导出对于线性调频脉冲信号电离层介质色散特性引起的合成孔径时间内多普勒频移误差的表达式。

It not only includes the "highly resemble" jamming signals generation by adding distance, azimuth, velocity and envelop deceiving information to the original captured radar transmitted pulse, but also includes the "covering" jamming signal generation by an modulation which will get an unmatched processing result in the radar receiver's match filter.

提出&高逼真欺骗干扰&和&掩护式欺骗干扰&的概念，详细阐述了&预警雷达高逼真及掩护式欺骗干扰技术&的原理，具体内容包括对雷达实现距离、方位、速度、幅度起伏等&高逼真&欺骗信息调制，以及利用脉冲压缩失配法产生多目标干扰回波以完成&掩护式&欺骗信息调制。

Since the harmonic spectrum of ac-side phase voltage of PWM rectifier is influenced not only by pulse modulation style, but also by the parameters of close-loop adjustors, a three-phase voltage source inverter controlled by TMS320F2812 has been built to obtain the harmonics purely generated by SVPWM and verify the algorithm.

由于PWM整流器交流侧相电压的谐波频谱不仅与脉冲调制方式有关，还受到闭环调节器参数的影响，因此该文搭建了以TMS320F2812为控制核心的三相电压型逆变器系统以得到单纯由SVPWM产生的谐波频谱，并对该算法进行验证。

Since the harmonic spectrum of ac-side phase voltage of PWM rectifier is influenced not only by pulse modulation style, but also by the parameters of close-loop adjustors, a three-phase voltage source inverter controlled by TMS320F2812 has been built to obtain the harmonics purely generated by SVPWM and verify the algorithm. Power analyzer PZ4000 has been adopted to acquire experimental results.

由于PWM整流器交流侧相电压的谐波频谱不仅与脉冲调制方式有关，还受到闭环调节器参数的影响，因此该文搭建了以TMS320F2812为控制核心的三相电压型逆变器系统以得到单纯由SVPWM产生的谐波频谱，并对该算法进行验证。

Introduces the height finding theory of the continuous wave frequency modulation altimeter and the pulse radar altimeter,analyzes the reason why the two kinds of altimeters were used in complex terrain to cause errors,and also gives out the experiment result that the plane mounted with the two kinds of altimeters flew in complex terrain section occasion.

介绍了调频连续波高度表和脉冲雷达高度表的测高原理，分析了两种体制高度表在复杂地形下使用时产生误差的原因，并且给出了两种高度表在复杂地形剖面场合下的机载试验结果。

When communication by pulses was introduced, the amplitude, frequency and pulse width become possible modulation options.

当脉冲的沟通被介绍的时候，广阔，频率和脉冲宽度变成可能的调音选项。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。