查询词典 cross correlation

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。

Information of system auto and cross spectrum, auto and cross correlation. coherent function, signal to noise ratio, frequency response and impulse response was established to help the study and arrangement of the module components.

由力规及加速规两量测之时域讯号，经快速富利叶转换，计算其自频谱及互频谱，再经反富氏转换回时域之自相关及互相关函数、相通函数、讯噪比、频率响应函数、脉冲响应函数。

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 generalized chirp-like sequence has the ideal periodic auto-correlation function, optimum periodic cross-correlation function and low peak-average power ratio.

广义线性调频序列具有理想的周期自相关特性和最优的互相关特性，以及低峰均功率比特性，因而被用作训练序列来估计每个用户的时间偏移。

This method, based on the normalized cross-correlation function, is the modified Speckle Pattern Correlation method in the application of the digital image processing technique to the speckle pattern metrology.

该法实质上是借助数字图像处理技术，通过物体位移前后二个散斑场之间的相关性来进行位移测量方法的发展。

A new de-correlation DOA estimation algorithm was proposed. It was based on the cross-correlation vector Toeplitz matrix reconstruction.

针对相干信号源的波达方向角估计问题，提出了一种能有效解相干的互相关矢量Toeplitz矩阵重构算法。

The content involves Digital Filter, Auto Correlation, Cross Correlation, mean and standard deviation, probability density and probability distribution statistic, as well as Auto Power Spectrum based on Fast Flourier Transfer, Correct Power Spectrum, Cestrum and Frequency Response. The Short-time Flourier Transfer and Wavelet Transfer are included in the analysis program.

具体内容包括：数字滤波、时域加窗、自相关计算与互相关处理、均值和方差计算、概率密度和概率分布统计，快速傅立叶变换基础上的自功率谱、互功率谱、频率响应函数、相关函数、倒频谱分析；基于短时傅立叶分析的联合时频分析、小波变换等。

The convolution and correlation are identical under a certain condition. In this condition, the interaural cross-correlation coefficient of an anechoic source convolved with the BIRs can be described by the IACC of BIRs and by the effective duration τe of ACF of the anechoic source.

在特定条件下，卷积与相关是等同的，此时，干信号与BIRs卷积后的IACC可直接由BIRs导出的IACC与干信号的ACF的有效时间τe来表示。

Compared with extended quadratic congruence codes,EHLC has large code cardinality,but has a little poor performances of auto correlation and cross correlation.

用该码作为时间扩频伪随机序列和以素数码作为波长跳频伪随机序列，再构成一种新的二维光正交码 EHLC/PC。

Based on quadratic congruences, a family of codes which have large capacity, good auto-correlation and cross-correlation properties is constructed in frequency domain.

在二次方一致性的基础上，构造了一种容量大、自相关和互相关特性好的码族。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。