查询词典 spectral

By adopting relationship in frequency domain coherence analysis method is presented on the thesis for conventional fMRI and resting-state fMRI. Otherwise I use cross spectral density function in the coherence analysis method to discuss the phase delay and phase lead.

本篇论文采用同调性分析的方法探讨频率上相关性的方法研究一般功能性影像与平静状态功能性的影像并藉由同调性分析里交互频谱密度函数来研究信号之间相位差的问题。

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 coordination polymer is characterized both by spectral methods and X-ray single crystal diffraction.

确定了这个配位聚合物的单晶结构，进行了光谱研究。

The Geo-RS model of biomass is not only considered the vegetation spectral ,but also the other relative information, the accuracy of this model is better than the cubic curve fitting, but workload is large and the model is complex .

生物量的遥感地学模型由于不仅仅考虑到了植被的光谱信息，也考虑到了其他的相关信息而反演精度高于三次拟合曲线，但是工作量大，建模复杂。

They process the hyperspectral image of the Cuprite derived by AVIRIS using the spectral unmixing method for mineral mapping.

最后对AVIRIS获取的Cuprite地区的矿物质进行混合光谱分解，结果可靠。

In part three, the absorption spectral behavior of binding reaction of cuprum- p-nitro-chlorophosphonazo Cu(Ⅱ-CPA-pN complex on bovine serum albumin was investigated.

第三部分：研究了蛋白质与Cu与对硝基偶氮氯膦的相互作用，发现蛋白质的加入能使配合物溶液的紫红色褪为紫色。

Primary tests of the device show that it has low dark current, high spectral sensitivity, very fast response speed, and quite small crosstalk between its neighbouring units.

通过对其主要的性能进行的特性测试表明，该探测器具有较低的暗电流、较高的光谱灵敏度和较快的时间响应，并且相邻单元之间的串扰也很小。

First, a cuvette filled with distilled water must be scanned as a blank to provide a spectral

首先， 要扫瞄一个装有蒸馏水的比色皿作为空白，以提供一个光谱背景。

First, a plastic cuvette filled with distilled water must be scanned as a blank to provide a spectral background.

首先，要扫瞄一个装有蒸馏水的塑料比色皿，它是作为光谱背景的。

Based on the spectral correlation theory of CS signal,a cyclic spectrum detection method of SS signal using acousto-optic signal processing technique was presented.

基于循环平稳随机信号的谱相关理论，提出了一种采用基于声光信号处理技术的扩频信号循环谱检测方法。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了