查询词典 power frequency

The transmit part adopts the phase-locked loop pattern of frequency synthesizing technology and uses the MC145152 and MC12022 chips to compose the phase-locked loop.It locks the frequency of the carrier-wave at 35MHz.The stabilization of the carrier-wave can be 4×10-5,the accuracy can be 3×10-5.The frequency modulation and the confection of the carrier-wave are realized by the capacity-changing diode V149 and the integration voltage-control oscillator MC1648 chip.The end power amplifier uses the audion 2SC1970 to make it work in the third magnifying state,it improves the efficiency of the magnifier and the power of the output reaches the design demand.

发射部分采用锁相环式频率合成器技术， MC145152和MC12022芯片组成锁相环，将载波频率精确锁定在35MHz，输出载波的稳定度达到4×10-5，准确度达到3×10-5，由变容二极管V149和集成压控振荡器芯片MC1648实现对载波的调频调制；末级功放选用三极管2SC1970，使其工作在丙类放大状态，提高了放大器的效率，输出功率达到设计要求。

At first, setting up the arith relation between the signal input and the signal output of the generalized multi-carrier system of the Discrete Fourier Test spread-spectrum; then setting equilibria parameters of the frequency field equilibria subcarrier of the generalized multi-carrier system of the DFT spread-spectrum according to channel frequency response, channel noise variance and equilibria method; then calculating average power of useful signal, interferential average power between signals as well as noise variance of the generalized multi-carrier system receiving terminal of the DFT spread-spectrum according to the arith relation as well as the frequency field equilibria parameter, and recomputing available signal information noise ratio, so as to calculate the available signal information noise ratio of the generalized multi-carrier transmission system accurately, the method for estimating the available signal information noise ratio can be used for link self-adapting transmission solution of the generalized multi-carrier system based on Discrete Fourier Test spread-spectrum and radio material management.

一种DFT扩频的广义多载波系统的SINR估计方法，其通过首先建立所述离散傅立叶变换扩频的广义多载波传输系统的信号输入输出之间的数学关系，然后根据信道频率响应、信道噪声方差和均衡方法，设定所述DFT扩频的广义多载波传输系统的频域均衡子载波的均衡系数，再根据所述数学关系及所述频域均衡系数分别计算所述DFT扩频的广义多载波传输系统接收端有用信号的平均功率、信号间干扰的平均功率以及噪声方差，再计算有效信干噪比，如此以实现对广义多载波传输系统的有效信干噪比的准确计算，该有效信干噪比估计方法可用于基于离散傅立叶变换扩频的广义多载波传输系统的链路自适应传输方案和无线资源管理方面。

PYX1-S type signal power supply panel is a special equipment for eight in formation automatic block with audio frequency shift modulated track circuits.It can supply power for signal lighting,track circuit,audio frequency shift relay circuit,approaching circuit,audio frequency shift control and detecting circuit.

PYX1-S型八信息移频电源屏是八信息自动闭塞的配套设备，可为信号点灯、轨道电路、移频继电器电路、接近电路移频控制检测电路提供电源。

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。

Limits of technical index frequency: 100kHz~50GHz, depend on probe power limits:- 70~+44dBm(100pW~25W), depend on probe power probe: As compatible as probe of HP8480 series power dynamic limits: 50dB, 10dB pace takes indication unit: Absolute power: W, DBm; Relative to power: Per cent, DB resolution: In resolution of logarithm mode optional 0.1, 0.01 with 0.001dB; 1% what perhaps be complete scale in linear mode resolution, 0.1% with 0.01%.

技术指标频率规模：100kHz~50GHz，取决于探头功率规模：-70~+44dBm(100pW~25W)，取决于探头功率探头：与HP8480系列功率探头兼容动静规模：50dB，10dB步进显示单元：相对功率：W，dBm；相对功率：百分比，dB 分辨率：在对数模式可选择的分辨率0.1，0.01和0.001dB；或者在线性模式分辨率为全刻度的1%，0.1%和0.01%。

In recent years, SiC FET power transistor and GaN high electron movability power transistor represent the third generation semiconductor-wide bandgap semiconductor power devices, have advantages of high breakdown voltage, high power density, as well as high output power, high operation efficiency, high operation frequency, wide instant aneous bandwidth, operation in high temperature environment and strong ability of resisting radiation.

近年来以SiC场效应功率晶体管和GaN高电子迁移率功率晶体管为代表的第三代半导体－宽禁带半导体功率器件具有击穿电压高、功率密度高、输出功率高、工作效率高、工作频率高、瞬时带宽宽、适合在高温环境下工作和抗辐射能力强等优点。

In the design of the power supply, the main circuit topology frame uses half-bridge series resonant switching and parallel load connection, in which, an IGBT is adopted as the power switches, and features high operation frequency, high output power and fast response. In addition, the IGBT in the switch mode power supply has no hard turn-on or turn –off situation in transition, thus the disturbance to the power system is avoided.

相应的激光电源采用半桥软开关技术，串联谐振并联输出，IGBT 为主控制元件，实现了高频工作、高功率多路输出，响应快速；脉冲模式工作时避免了开关管的硬开关，减小了高次谐波对电网的干扰；无需镇流电阻也可实现气体稳定放电等特性。

according to the users′ actually demand for uninterruptible power supply for loads,the internal structure of digital generator is analysed and the reason for its uninterruptible function can′t be achieved.a design of the uninterrupted power supply system which transformed from the digital generator is proposed.the system uses the inverter of generators,ac through inverter for loads,at the same time,charges the battery as ac is normal.inverter the battery dc converters to ac for load,meanwhile,starting generator,when power failure.the system applies uninterruptible power for load,whether the ac is normal or abnormal,and design voltage and frequency stabilization,output zero-interrupted,battery charging and discharging management.without requiring purchase an uninterruptible power supply separately,this design can avoid duplication of investment and wasting of resources.

快速安全提高汽轮发电机转子检修质量。。。摘要：针对用户对负载供电不间断的实际需求，分析了数码发电机的内部结构及其不能实现供电的不间断性能的原因，提出一种由数码发电机改造组成的交流不间断供电系统的设计方法。该设计利用发电机内部的逆变器，在市电正常时，由市电经过逆变器给负载供电，同时给蓄电池充电；在市电断电时，一边启动发电机，一边由蓄电池的直流电通过逆变器转换成交流电供负载使用，实现无论市电正常还是异常，系统对负载提供不间断电源。设计对市电进行稳压、稳频、输出零切换、蓄电池的充放电管理等新功能。此设计无需单独购买不间断电源，避免重复投资和资源浪费。

The purpose: AC filter capacitor complete unit is connected into the power system of power frequency to filter harmful harmonic current out in power system and improve the quality of power, increase power factor.

产品用途：交流滤波电容器成套装置接于工频电力系统中，有以滤除电力系统中有害的谐波电流，改善电能质量提高功率因数。

As communicating madia is power line ,which needn't the extra line , and not take in the existing frepuncy resource.In the power system ,the power line is using steadily and reliable high press power line as the signal's trans madia,which may save a great deal of the building investment,in additional to the route is suitble ,scurity and may reuse the far away mobile signal ,of which makes this power system develop a particular communicating way ,while in number micro-wave,one point more address,optical fiber,super-high frequency repeatly renew today ,which also last developing.

由于电力线载波在电力系统中使用坚固可靠的高压电力线作为信号的传输媒介，可节省大量的通道建设投资，再加上电力线载波信息传输稳定可靠，路由合理，安全保密以及能够同时复用远动信号等特点，使得这种电力系统独有的通信方式在数字微波，一点多址，光纤，特高频等通信方式相继出现的今天仍得到持续的发展。

I think people in this lifetime in a rebirth.

我觉得人在这一生里其实也在轮回。

He had to tie her hands together.

他不得不把她的双手绑在一起。