载频

With high carrier frequency in future communication systems and long OFDM symbol caused by and large subcarrier number, high mobile velocity that will result in fast-fading channels, will make the OFDM system suffered by the intercarrier interference.

随着未来系统的高移动速度，高载频和大子载波数所导致的长OFDM符号都将使系统的性能正越来越深地受到快速时变多径信道所带来子载波间干扰的影响。

Intelligent Microzone Wireless Coverage System is a Microzone Wireless Coverage System dynamic, self-allocated traffic and carrier-frequency resource.

智能微小区覆盖系统是一种可动态的、自主调配话务和载频资源的微小区覆盖系统。

From the angle of a beam-forming, the cross- range focusing principle of the synthetic-aperture radar based on nonsinusoidal waves is studied. The expressions of antenna pattern for both rectangular signa l and Gaussian signal are presented. Compared with the conventional narrow bandw idth SAR whose cross-rang resolution is determined by the carrier frequency, th e cross-range resolution of the nonsinusoidal SAR is affected by the signal ban dwidth.

为研究非正弦波SAR的方位向分辨力，从波束形成的角度分析了非正弦波SAR的方位向聚焦原理，导出了基于矩形脉冲和高斯脉冲的合成孔径天线阵列方向图表达式，并与常规窄带SAR进行比较，指出影响非正弦波SAR方位向分辨力的主要因素为合成孔径长度和信号带宽，而与信号载频无关。

Experiments are done. The results of experiments are satisfactional and consistent with theory. The results of experiments indicate the design of the hydraulic loading is right.

利用所开发的单片机测控系统对液压加载系统进行了阶跃响应和频域响应试验研究，试验结果表明，液压加载系统完全能满足液压悬挂系统的要求，并且与理论分析结果一致，说明液压加载系统的设计和控制方法是正确的。

In the third part of this paper,Aiming at the different characteristic of theextended target spectrum ,this paper discussed the detecting and precised measuring the extended spectrum of the target.

在本章的第三部分，本文针对弹载高重频脉冲多普勒体制雷达展宽回波信号频谱的不同特点，讨论了在不同条件下弹载高重频脉冲多普勒体制雷达对展宽信号频谱的检测及精确测量的问题。

The modulator (25) may also include an offset circuit (24) so that the modulated waveform includes a carrier frequency indicator.

所述调制器(25)还可以包括偏置电路(24)，使得调制波形包括载频指示符。

When the circuit is shorted, the 20kHz carrier frequency signal indicator will goes off and gives the commend for power cut off. The audible and light signals will be also given.

遇有短路，20kHz载频信号消失，给出切断电源的执行指令，并给出声、光报警。

This paper proposes a carrier frequency offset estimation algorithm for interleaved multi-user OFDM.

提出一种针对多用户交织OFDM 载频偏移估计的算法。

BACKGROUND OF THE INVENTION For the compensation of carrier-frequency fluctuations due to changes in ambient temperature it is customary to use a resistance network including one or more thermistors disposed in the vicinity of the oscillator so as to sense the temperature changes affecting the quartz crystal which acts as frequency-controlling element thereof.

本发明的背景为了修正因周边温度改变而产生起伏的载频，一般的惯用法是使用一个电阻网络，其中包括一个或多个配置在振荡器附近的热敏电阻，以便检测能够影响作为频率控制的水晶体的温度变化。

Based on one-cycle control having such merits as anti-perturbation of source, fast dynamic response, robustness, constant frequency, but when converter works in light load its power factor becomes very poor. The modified OCC was proposed, adopting feed-forward compensation control improves influence of power factor at light load, further study adopting independence saw tooth wave completely eliminate influence of power factor at light load.

基于单周期控制有源前端变换器具有抗电源扰动能力强、动态响应快、鲁棒性强、恒频控制等优点，但在轻载时变换器的功率因数变差，提出了改进OCC策略，采用前馈补偿控制改善轻载时对功率因数的影响，进一步研究采用独立的锯齿波电路完全消除轻载时对功率因数的影响，建立改进OCCAFE变换器的数学模型。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。