查询词典 radio-frequency spectrum

The invention discloses a multi-cell pilot frequency distribution method applied in an orthogonal frequency-division multiplexing system, which comprises the following steps: generating at least two different original frequency hopping sequences according to a predetermined pilot frequency domain; generating a combined frequency hopping sequence (having length greater than that of the original frequency hopping sequences) from at least two different original frequency hopping sequences; generating different pilot frequency structures satisfying collision threshold requirements based on the combined frequency hopping sequence; and distributing the generated pilot frequency structures to each cell.

本发明公开了一种多小区导频分配的方法，用于正交频分复用系统，按照预定的导频频域间隔生成至少两种不同的原始跳频序列；将至少两种不同的所述原始跳频序列生成组合跳频序列，所述组合跳频序列的长度大于所述原始跳频序列的长度；基于所述组合跳频序列生成满足碰撞门限要求的不同导频结构；将所述生成的导频结构分配给各小区。

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。

The study about the flux and index of gamma-ray loud blazars show:(1)there is significant correlation between the luminosities in gamma-ray and VLBI radio energy band;(2)there are strong anticorrelarions among the observed indices of soft X-ray, hard X-ray and gamma-ray. For the FSRQs, the whole X-ray emission was contributed by synchrotron self-Compton emission, for the HBLs, the X-ray emission was dominated by synchrotron emission while the soft X-ray emission is dominated by synchrotron emission and the SSC emission dominate the hard X-ray energy band for LBLs;(3) there are strong radio-radio and radio-optical flux correlations for the quasar 3C 273. The higher frequency emission leads those in lower frequency. The multi-band complex indices strongly correlated with the high frequency flux which implies that the object is becoming bright when the energy spectrum is harden.

通过对γ噪Blazar天体的谱指数、流量的相关研究，发现（1）51个样本blazar的γ射线光度与VLBI光度之间存在显著相关；（2）软X、硬X以及γ波段的观测谱指数之间存在较强的反相关，对FSRQs，无论是硬X射线还是软X射线的辐射都是逆康普顿辐射的贡献，而对于HBLs来说，则是同步辐射的贡献，对LBLs，在软X射线波段以同步辐射贡献为主，在硬X射线能区以逆康普顿贡献为主；（3）3C 273的射电各个波段以及光学之间存在强相关，高频辐射一直领先低频辐射，3C 273的多波段复合谱指数和高频流量之间存在强的反相关，意味着当能谱变硬时对象变亮。

This system ofcompatible electromagnetism of frequency spectrum has someimportant functions listed as follows:(1) Analysis disturbance of the same or adjacent frequencies (2) Analysis of performance of radio link (3) Analysis of intermodulation (4) Automatic selection of frequency(auxiliary assignment of frequency)(5) Prediction of region of radio field intensity (6) Harmonization of frequency border (7) Analysis and design the system of microwave and satellite earth station.(8) Generate photographs This paper realizes the function of harmonization analysis ofthe system of microwave and satellite earth station. The concretework includes:(1) Based on the propagation model of radio wave,computing the absorption loss of atmosphere of microwavecommunication system and its fading, simulating the receivingvoltage and realizing the computation of disturbance andharmonization between microwave station and earth station.

频谱电磁兼容分析系统主要实现以下几个功能：⑴同、邻频干扰分析⑵无线链路性能分析⑶互调分析⑷频率自动选择⑸场强覆盖预测⑹边界协调⑺微波与卫星地球站系统设计和干扰协调分析⑻图形制作功能本文做为全省建设的电磁兼容分析系统的一部分，实现了微波站与地球站干扰协调分析这一功能，具体有：⑴以无线电波自由空间传播为模型，对微波通信系统的大气吸收损耗和衰落储备量进行了计算、对接收电平进行了模拟仿真，实现了微波- I -吉林大学硕士学位论文 Abstract站与地球站之间的干扰与协调计算。

The key problems of software radio and direct sequence spread spectrum range used in high range radio fuze are discussed. The effects of doppler frequency and carrier's initial random phase are analyzed. A new direct sequence spread spectrum algorithm based on software radio is proposed, by using differential encoding and quadrature demodulating, the effects of doppler frequency and carrier's initial phase on the output of inference filter are eliminated successfully.

研究了软件无线电和直接扩频测距技术在大炸高无线电引信应用中的关键技术问题，分析了由于多普勒效应引起的载波频偏以及载波随机相位对测距的影响，提出了一种基于软件无线电的直接序列扩频解调算法，通过采用差分编码和正交解调的方法，消除了多普勒频偏和载波随机相位对测距的影响。

Aiming at this problem, the concept of the second order power spectrum was proposed based on the characteristic of the amplitude tune with periodical notch spectrum in thin layer and theoretically researched. The corresponding relationship between the thickness of thin layers and the maximum value of second order power spectrum was established. The theoretical criteria and method for the thickness estimation by second order power spectrum were given. The second order power spectrum map is made by the energy relationship between the thickness of thin layers and the second order power spectrum, and the time responding to strong energy on the map is the time of thin layer.

为此，从薄层振幅调谐具有周期性陷频谱特征出发，提出了二阶功率谱的概念，从理论上对薄层的二阶功率谱特征进行了研究，建立了薄层厚度与二阶功率谱极大值之间的对应关系，给出了利用二阶功率谱进行薄层厚度预测的理论依据和方法，即根据薄层厚度和二阶功率谱的能量关系制作二阶功率谱图，图上强能量团对应的时间即为薄层时间厚度。

The effect of endoscopic plasma radio-frequency therapy for gastrointestinal polyps is obvious and very safe, and bequite with high-frequency eletrosetion, plasma radio-frequency electrosetion could be used on special locations and excelled to the comparisonal group in therapic time,be good for clinical using as the preferred method to therapy for gastrointestinal polyps.Key words: polypus recti; endoscope; radio–frequency therapy; cutting

等离子射频技术应用于消化内镜下息肉切除，具有安全、疗效可靠，其疗效与高频电切相当，且能够在内镜反转状态针对胃底、直肠下段等特殊部位息肉实施有效切除，在术后愈合时间上明显优于对照组，可尝试作为内镜下切除消化道息肉的首选方法，对具有消化内镜诊疗条件的医疗机构，值得临床推广应用。

Observing the extragalactic radio sources in both radio and optical wavebands is the important method to construct the relationship between radio and optical reference system. Since the precision of radio positions of radio sources is better than lmas, determination of optical positions of radio sources is the key step.

实现射电与光学参考系连接的一个重要手段是在两个波段观测河外射电源，由于射电源的射电定位精度已达亚毫角秒，因此河外射电源的精确光学定位是关键。

Through simulation and computation, some critical values to contral interferences are obtained. These values have directive significance to the design and deployment of WRAN.(4) New methods to measure and analyze spectrum aredevelopedAccording to the shortages of previous spectrum measurements, new methods to measure spectrum occupancy in wide-band and multi-point synchronously is proposed in this dissertation, and the tests last a whole week; the relativities of licensed services are considered when test points are selected. More importantly, data mining and in-depth analysis are carried out with the huge amounts of test data, and a channel analysis method using Channel Vacancy Duration and Service Congestion Rate are proposed. The spectrum relativities of 3-dimension in time, space and frequency are researched also. The correlativity between channel state and history information is discoved, and which will provide the scientific basis to channel modeling, spectrum analysis and decision of CR users.

4提出了频谱测量与分析的新方法针对以前频谱测量工作存在的不足，本文提出了多点同时广域频谱测量方法，测量工作持续了一周的时间，同时考虑了测量地点的选取和频谱授权业务之间的相关性；对测量得到的海量数据进行了数据挖掘和深度分析，提出了使用信道空闲时间(Channel VacancyDuration，CVD)和业务拥塞率(Service Congestion Rate，SCR)进行信道分析的方法，研究了频谱之间的时间、空间、和频率三维立体的相关性，发现了信道状态和历史信息的关联性，为CR用户的信道建模、频谱分析和决策提供了科学的理论依据。

Meanwhile, 2-D spectrum and the corresponding parameters of irregular wave transformation (predominant wave direction and mean wave direction, peak frequency and peak spectrum density, spectrum width, mean period, mean wave length, mean wave crest length and 3-D index and so on)、 1-D frequency spectrum and the corresponding parameters and numerical results of wave height、 wave direction of regular wave transformation are offered.

提供不规则波传播变形二维谱及其谱参数(主波向及平均波向、峰频及谱峰值、谱宽度、平均周期、平均波长、平均波峰长度及三维性指标等等)，不规则波一维频率谱及其谱参数和规则波变形的波高、波向模拟值。

The use of the web to spread fears that flicking the switch on the LHC could create a Black Hole that could swallow up the Earth particularly concerned him, he said.

他说，使用互联网散布恐慌说启动LHC会生成一个可能吞噬地球的黑洞的做法让他感到忧虑。

Not a single word have I written down.

我一个字也没有写下来。