干扰

The interference of fermentation broth to CTAB measurement was further observed. It is revealed that Mg2+ concentration exhibits a significant impact on CTAB results, but glucose, arabinose and D-glucuronic acid not.

进一步研究了发酵液各成分对改良CTAB方法的干扰，结果表明，葡萄糖、阿拉伯糖、D葡萄糖酸前体等对CTAB浊度法没有干扰，但Mg2+等具有较为明显的干扰。

But this kind of open emission and reception system in High frequency communication has to face two challenges: firstly, natural interference from atmospherics and industry; secondly, tracing, blocking and multipath interference from enemy.

但这种开放式的发射和接收电磁波的通信，特别是在短波通信领域，不仅易遭到天电、工业等自然干扰，而且还要遇到敌方人为的跟踪、阻塞干扰以及多径等各种干扰。

This paper proposes a non-linear adaptive filtering method based on analyzing the performance of the conventional adaptive methods in the cases of that the NBI can be modeled as a single tone,an autoregressive stochastic process or narrow band BPSK digital modulation signals.

在分析线性自适应滤波抑制单频干扰、自回归过程窄带干扰和窄带BPSK调制信号干扰的性能的基础上，提出了一种非线性自适应波抑制方法。

In Chapter 2, a simplified analytical model is presented for the analysis of the BVI mechanism, adopting the Beddoes' prescribed wake model. By this model, the azimuthal location and miss-distance of the BVI and the radiation directivity of the BVI noise are calculated and discussed, and some conclusions are obtained.

在第二章，使用Beddoes预定尾迹模型，建立了一个用于旋翼桨-涡干扰特性机理分析的简化数学模型，分别对旋翼桨-涡干扰位置、桨-涡干扰距离和声辐射方向性等进行了计算和分析，得出了有意义的结果。

The computer simulations show that AIC-SOCS can reject the interference more efficiently compared with the Adaptive Interference Canceler based on Second Order Statistics because is independent of uncorrelated Gaussian noise, and it can reject interference as efficiently as AIC-FOS.

仿真实验表明，AIC-SOCS的性能和AIC-FOS的干扰抑制性能相当，表现出比基於二阶累积量的自适应干扰对消器更优良的干扰抑制性能。

DRFM is the best sources of noise and deception jamming, it has become powerful means to counterwork new system Radar.

高性能的数字射频存储器是产生最佳噪声干扰和最佳欺骗干扰的干扰信号源，是对付新体制雷达的有力手段。

The proposed method first employs covariance matrix tapers to obtain the interference covariance function and its corresponding spatial spectrum in non-ideal scenarios.

该方法首先利用协方差矩阵加权得到非理想情况下的干扰协方差函数和对应的空间谱，然后根据周期延拓后的干扰空间谱估计干扰自由度。

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。

Crosswise coupling disturbance of a loading system with multiple degree of freedom is analyzed.

针对多自由度加载系统中存在的横向耦合干扰问题进行了理论分析，推导出横向耦合干扰的数学计算公式，并提出了横向耦合干扰的补偿方案

A general formula is derived by using power series by which we can predict the amplitude and power level of PIM (especially for odd-order PIM).

采用合成干扰模型假设和特征函数方法简化了PIM问题，对包括PIM干扰在内的总干扰的统计特性进行了数学分析，进而对无源互调对通信系统的抗噪性能的影响做了数值模拟。

He knows that he's one of the mostdominant players in the NBA right now.

我知道他现在是联盟里最有统治力的球员之一了。

Using analysis method of BCG , the dissertation analyzed the management of voluntary service organizations .

利用BCG分析方法对我国的志愿服务组织管理进行了分析。