谱

Stationary process: spectral decomposition of covariance function, spectral decomposition of stationary process, linear time invariant system, ergodic theorem, sampling theorem.

平稳过程：协方差函数的谱分解，平稳过程的谱分解，线性时不变系统，遍历定理，采样定理。

This paper discusses the estimation method of wave spectrum by covariance functional method.

黄海；平均波高；海浪谱；协方差函数；海浪频谱；本文用协方差函数法探讨了海浪谱的估计方法。

To solve the problem that the-spectrum estimation performance based on covariation under the-stable noise environmentbecomes obviously worse when the distribution parameter is small,a method of fractional low-order covariance spectrum estimation was proposed.

针对在分布参数值较小时稳定分布噪声下基于共变的谱估计性能较差这一问题，提出了一种分数低阶协方差谱估计方法。

The method, which is capable of effecting very good separation of phenol and the 3 cresol isomers under the same chromatographic conditions, can be used to determine phenolic compounds in phenolic tar by external standard, and to analyze these compounds in the toxic leaching solution of the tar.

摘 要：建立了酚焦油中酚类物质质量分数测定和浸取毒性测定的气相色谱法，此法可以在同一色谱条件下对酚焦油中的苯酚及邻、间、对甲酚实现很好的分离，利用外标法分别进行定量分析，并对酚焦油浸取液中相应组份进行测量。

In the first session the fans vibration on-line monitoring system is realized with VC language, also compile auto power spectrum density function, cross power spectrum density function, autocorrelation function and cross correlation function etc spectral analysis function to carry through simple offline fault diagnosis.

首先用稳定性强、扩展性好的VC++语言开发了通风机振动在线监测系统，并编写了自功率谱密度函数、互功率谱密度函数、自相关函数和互相关函数等频谱分析函数来进行简单的离线故障诊断。

Through data processing arrangement and cross correlation function calculation designed on PC,flight time spectra of 252Cf Source fission neutron and gamma ray can be obtained.

实验结果表明，该系统可以获得252Cf自发裂变中子源的中子、γ射线飞行时间谱，与经典的飞行时间谱测量方法相比较，其图谱表达及数值结果有着很高的吻合度。

A method of cross power spectral density between responses is derived and a poly reference modal analysis method using cross power spectral density method in frequency domain is presented in this paper.

对各测点响应的互功率谱密度函数进行了详细推导，提出了一种基于互功率谱密度的频域多参点辨识法，这意味着许多原本利用频响函数的传统频域识别法可以很容易地用于工作状态下的模态识别，大大开阔了未知激励下模态识别的视野。

The Cholesky decomposition of cross spectral density matrix was approximated and reduced, and then the modified spectral representation method is efficient and requires less computer memory, which is suitable for simulating spatial wind fields of long span bridges.

针对现有Deodatis方法模拟大跨度桥梁空间脉动风场中存在的计算量问题，通过对谱分解矩阵引入插值近似，减少谱分解的次数，从而提高该谐波合成法的计算效率，并节省内存花费，实现了对三维空间脉动风场的有效模拟。

The main job and contribution of this paper are as follows:Based on narrowband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, compute the cross-correlation function of FH signals from multichannels, then we get the cross power spectral density matrixCSDM Secondly, select the hops of FH signals from the CSDM via processing and analyzing the CSDM, meanwhile reduce the influence coming from noise, fixed frequency signal and other interferences; Lastly, estimating the DOA of every hop and according to the DOA, we can separate the hops, get the number of FH signals and their parameters. Propose a new method for designing the threshold in FH signal detection. This method makes it easy to get the threshold by theoretic computing and it can extremely reduce the interference of non-FH signals.Based on broadband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, get the DOA of the signals by wideband spatial spectrum estimation; secondly, separate the signals by spatial filtering using wideband beamformer; Lastly, we propose two methods for FH signal blind detection and blind parameter estimation, one is for several constant hop-rate FH signals whose dwell-time are different and another is for a single FH signal whose hop-rate is alterable.By employing spatial interpolation in broadband signal beamforming, it can reduce the number of antenna elements and corresponding RF modules, A/D converters, etc. It can also eliminate the mutual coupling between antenna elements while getting the narrower main beamwidth and lower sidelobe level.

本文的主要研究工作和贡献如下：●提出了一种基于窄带处理的FH信号盲检测和参数盲估计的实现方法，即首先求出多路信号之间的互相关，进而得到互功率谱密度矩阵，然后通过对CSDM进行对折处理来抑制噪声、定频信号及其他干扰的影响，并将所有属于FH信号的hop(每一跳的驻留时间在时频图上持续的线段)从CSDM中筛选出来，最后用阵列信号处理中的到达方向估计理论在频域中估计出各个hop的方向参数，利用方位信息完成FH信号分离并得到FH信号的数目及其各自的参数集；●提出了一种确定FH信号检测门限的策略，该策略不仅使得检测门限能够通过理论计算得到，而且还显著地抑制了非跳频信号的干扰，从而能有效地检测出FH信号；●提出了一种基于宽带处理的短波FH信号盲检测和参数盲估计的实现方法，即首先利用宽带空间谱测向技术得到接收信号的DOA，然后采用宽带波束形成技术对特定方向进行空间滤波，实现多个信号的分离，最后分别提出了两种FH信号的盲检测和参数盲估计方法，第一种方法适用于空间某个特定方向上存在着几个驻留时间不同的恒跳速FH信号和其他干扰信号的混合信号，第二种方法适用于空间某个特定方向上仅含一个可变跳速的FH信号和噪声的混合信号；●将空间插值的概念和宽带波束形成技术结合起来，提出了一种基于频域处理的宽带恒定束宽的波束形成方法。

The integrated aberration-reduced gratings are the key elements in high capacity optical network using wavelength routing and forming the basis of an optical cross-connect, they are used in demultiplexer.

现代谱仪中的光电探测元件一般是平面型的，消像差光栅是平场谱仪的关键元件。微型消像差光栅也是光通讯中的无源波分复用器的核心元件。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。