高频率

Measure character: Frequency limits: CH1:dResolution of C ～ 225MHz frequency: 10 / second time-interval resolution : N/A measures speed: Can amount to 200 times measure / the second mixes in limits of the voltage on GPIB sensitivity : DC ～ 100MHz: 200MHz of ～ of 5Vac+dc 100MHz of 20mVrms ～±: 225MHz of ～ of 5Vac+dc 200MHz of 30mVrms ～±: Input of 5Vac+dc of 40mVrms ～± adjusts:(CH1 chooses) impedance, coupling: 1M Ω or 50 Ω, ac or Dc are low connect filter: 100kHz, but switch attenuation:× 1 or reference of × 10 exterior time base inputs: 1, 5, 10MHz sparks: CH1, to rising / drop the edge sparks, the percentage that uses signal n or absolutely voltage install n, setting sensitivity mixes to low, medium or tall gate start: Automatic, the hand is moved (setting gate time or resolution digit); Exterior, defer interface: Standard GP-IB(IEEE 488.1 and 488.2), take; of SCPI compatible language to say RS-232 power source only: 10 ％ of 100-120VAC ±, 50, 60 or 10 ％ of 400Hz ± 10 ％ of 220-240VAC ±, 50 or 10 ％ of 60Hz ± are suttle: 3kg dimension: 348.3mm of × of 212.6 × 88.5H

测量特征：频率规模：CH1：dc～225MHz 频率分辨率：10位/秒时候距离分辨率：N/A 测量速度：可达200次测量/秒在GPIB上电压规模和灵敏度： DC～100MHz： 20mVrms～±5Vac+dc 100MHz～200MHz：30mVrms～±5Vac+dc 200MHz～225MHz：40mVrms～±5Vac+dc 输入调节：(CH1选择)阻抗，耦合： 1MΩ或50Ω，ac或dc 低通滤波器： 100kHz，可切换衰减：×1或×10 外部时基参考输入： 1，5，10MHz 触发： CH1，对回升/回升沿触发，用信号电平的百分数或相对电压设置电平，设置灵敏度至低、中或高闸门和启动：主动，手动(设置闸门时候或分辨率位数)；外部，延迟接口：尺度GP-IB(IEEE 488.1和488.2)，带SCPI兼容说话；只讲RS-232 电源：100-120VAC±10％，50，60或400Hz±10％ 220-240VAC±10％，50或60Hz±10％净重：3kg 尺寸：212.6×88.5×348.3mm

The purpose of opening the orifice was to sluice. The influence of fluctuating pressure upon the dam was another problem which was concerned by engineer. The paper analyzed Shuangkoudu masonry arch dam. The result indicated that the dam natural frequencies which consider the dam and the reservoir water interaction have great different from the preponderant frequencies of fluctuating pressure, the dam's first rank of vibration was far away from the high energy region of the fluctuating flow, so the sympathetic vibration would not take place.

坝身开设孔口主要目的是为了泄洪，泄洪时水流脉动压力对坝体结构动的影响是设计人员关心的另一课题，论文针对双口渡浆砌石拱坝进行了分析，研究结果表明：在考虑坝体一库水相互作用时坝体自振频率和水流脉动压力的优势频率相差较大，坝体的一阶振动远离脉动水流的高能量范围，二者不会发生共振。

Taking the high precision on chip RTC as the time base control unit and using genetic algorithms to search the best OSCCAL register value, it will make the on chip RC oscillator generate a high precision clock for the MCU. This methord can be used fast and real time, so the CPU will get a stable clock source.

以AVR片内高精度时钟单元RTC为时基控制单元，以标准时间内MCU定时器的计数值为控制目标，采用遗传控制策略搜索对应MCU理想时钟频率的OSCCAL寄存器最佳设置值，快速、准确地对RC振荡频率进行校准，为CPU提供具有高抗干扰特性的精确时钟。

And this causes a frequency change Δf. The resonant point tracing algorithm describes how to detect Δf. So it can introduce a feedback frequencydifference -Δf through a closed loop to realize the resonant state o In the digitaldetection scenario, using staircase wave to replace saw tooth wave, it can overcome a lot of shortcomings in the analog system. The character of the staircase wave affects the detection precision directly. This thesis analyzes a high precision scenario producing a staircase waveform in detail. It can reduce the number of the bits in D/A converter greatly. This thesis proposes another method to improve the detection precision in case that the A/D converter has comparatively little number of bits, while this method will not increase the cost of the system greatly.

在谐振式光纤陀螺中，环形谐振腔的旋转使得谐振腔的谐振频率发生了变化，从而产生了一个与旋转速度成正比的频率变化值△f，谐振点跟踪算法描述了如何检测出△f，从而可以通过闭环在系统中引入反馈频差-△f，实现光路的谐振状态；在数字闭环检测方案中，用阶梯波作为反馈信号来代替锯齿波，可以克服原来模拟系统中锯齿波的很多缺点，阶梯波的性能直接影响着系统的测量精度，本论文详细分析了一种高精度阶梯波生成方案，使得所需D／A的位数大大降低；本文还分析了A／D转换器对系统测量精度的影响，提出了一种A／D转换器位数较少的情况下提高系统测量精度的措施，同时又不会增加太多的系统成本。

At present, the Legend main customers for the provision of various types of RFID gain ratio the high efficacy of microwave paragraph (2.4G frequency) reader, as well as independent research and development Legend of international general agreement to support a variety of ultra-high frequency tags ( 860-915MHZ frequency) RFID read professional adjustable head.

目前，凌讯公司主要为RFID客户提供各类增益比的高功效微波段（2.4G频率）读写器以及凌讯自主研发的可支持多种国际通用协议标签的超高频段（860-915MHZ频率）可调的专业RFID读头。

The method of equal accuracy frequency measure can remove the errors of unitage and keep the high accuracy constant in the whole measure frequency segment. So the signal frequency has measured is high or low can't influence its accuracy.

等精度频率测量方法消除了量化误差，可以在整个测试频段内保持高精度不变，其精度不会因被测信号频率的高低而发生变化。

We need frequencies even higher than those we call very high frequency.

我们所需要的频率甚至比我们称之为甚高频的频率还要高。

Because light has a very high frequency, it can carry a lot more data than microwaves or radio waves, which have much lower frequencies.

由于光的频率非常高，可以比频率低很多的微波或无线电波承载更多的数据。

Because light has a very high frequency, it can carry a lot moredata than microwaves or radio waves, which have much lowerfrequencies.

由于光的频率非常高，可以比频率低很多的微波或无线电波承载更多的数据。

The character of the system is as follow: the system can generate random wave signal, the frequency of output signal can be adjusted accurately, the stability of output frequency is very high.

本系统的主要特色：可以产生任意波形的信号，输出信号的频率可精确调整，且频率稳定度很高。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！