查询词典 frequency modulation

RF modules covering GSM, CDMA, TD-SCDMA, WCDMA, WLAN and Wimax wireless communications systems, active modules include power and frequency of the linear power amplifier, transceiver components, modules and integration of selected frequency modules, Passive radio frequency modules, including various types of filters, diplexers, a road, splitters and couplers; wireless network optimization campaign整机including PHS, GSM, CDMA, TD-SCDMA and WCDMA straight-machine, RF Rafah Yuan and indoor distribution systems, digital television, including digital TV mobile wireless transceiver modules, wireless transponders, digital mobile TV repeater, and so on.

射频模块涵盖了GSM、CDMA、TD-SCDMA、WCDMA、WLAN和Wimax等无线通信系统，有源模块包括各种功率和频率的线性功率放大器、收发组件、选频模块和一体化模块等，无源射频模块包括各类滤波器、双工器、合路器、功分器和耦合器等；无线网络优化系列整机包括PHS、GSM、CDMA、TD-SCDMA和WCDMA直放机、射频拉远和室内分布系统等；数字移动电视包括数字电视无线收发模块、无线转发器、数字移动电视直放站等。

Pitch frequency by the sound level of the object decision, high frequency sound on the high, low frequency sound is low, the existing international standard pitch was in May 1939 in London by the International Standards Association of a1 = 440 Hz.

音高是由发音物体振动频率的高低决定的，频率高声音就高，频率低声音就低，现行的国际标准音高为1939年5月国际标准协会在伦敦通过的a1＝440赫兹。

Each House Detective installation kit comes with three primary test instruments; a frequency agile signal level meter, a frequency agile radio frequency leakage detector, and a zero foot dead zone time-domain reflectometer; all three housed together in a durable hard case.

每家侦探安装套件具有三个主要的测试仪器，一个频率捷变信号电平表，一个频率捷变射频泄漏探测器和一个零脚死区时域反射计；所有三个关在同一个持久的疑难案件。

After transverse Zeeman effect is introduced to reduce the mode coupling, the laser could produce two orthogonal linear polarized components with 5MHz beat frequency. The effect of the magnetic field's direction to generation of the dualfrequency and the polarization property of the laser is investigated Based on theoretical study and experimental investigation to the beat frequency tuning character, a novel method for stabilizing the laser beat frequency is brought forward.

现代机械工业的发展使得机床、三坐标测量机等的运行速度已提高至1m/s，为适应这种发展趋势，本文研究了高频差（5MHz）激光干涉仪的光源、稳频和外差信号的处理等基本问题，建立了测量速度可达1m/s的高测速激光干涉仪，并对其在加工中心主轴热漂移测量系统和加工中心误差实时测量系统中的应用进行了研究。

We add a frequency compensation loop in an all digital CDR. This frequency compensation technique compensate large frequency variation in spread spectrum data.

在一全数位化的时脉与资料回复电路中，加上另一回路，以补偿在展频技术下产生的较大的频率变动。

Absolute frequency stabilization of diode lasers of wavelength nm grade are reported using the modulation transfer method .

阐述了利用调节及转换技术稳定激光二极管发射器的频率，这种发射器可以发射纳米波长的激光。

Frequency modulation ; magnetic rotation spectroscopy ; absorption line shape ; dispersion line shape.

频率调制；磁旋转光谱技术；吸收线型；色散线型

An expression for acoustic wave amplitude as a function of modulation frequency and relaxation time has been derived.

推导了光声信号振幅与入射光调制频率和样品分子振动－平动弛豫时间的函数关系。

The common equation of the evolution of spectrum caused by selfphase modulationis presented, which is the convolution of action spectrum and chirped spectrum caused by selfphase modulation when carrier frequency is single.

给出了由自相位调制引起的频谱演变的普遍表示，即单载频脉冲的SPM引起的啁啾频谱与光源的频谱的卷积，通过数值计算给出从相干脉冲到非相干脉冲的频谱演变规律。

NTSC uses a quadrature amplitude modulation with a suppressed color carrier and works with amotion frequency of approximately 30 Hz. A picture consists of 525 lines.

NTSC的色彩载波使用接近4.9MHz或3.57MHz的频率，它使用颜色载波进行正交调幅，画面运动频率约为30Hz，每幅画面有525线。

I can not negligent, he should do what?

我不能不在意了，他要做什么呢？

It is very dangerous to swim in the river alone.

一个人到河里游泳是很危险的。