阵的谱

The Airy function is used to calculate the plasma impedance and the grill-plasma scattering matrix is deduced, then the coupling properties of the HT-7 LHCD MJ launcher are studied with the antenna scattering matrix and the grill-plasma scattering matrix based on the liner coupling theory. The average power reflection coefficient, directivity, power spectrum are obtained for different edge plasma densities and for different phasings between main waveguides.

采用线型耦合理论，用艾黎函数计算了等离子体阻抗，推导出常规波导阵对等离子体的散射矩阵，并利用它和天线自身的散射矩阵研究了HT-7装置低杂波多结波导阵天线的耦合特性；计算了其平均功率反射系数、方向性系数和功率谱与等离子体边缘密度和主波导相位差等参数的关系。

A lake trial of three-element vector hydrophone linear array was carried out to test the validity and practicability of MUSIC algorithm.

为了检验矢量阵MUSIC空间谱方位估计算法的性能，进行了三元矢量阵的外场试验，对比了MUSIC空间谱估计以及常规波束形成的性能。

The estimation errors, including the finite difference approximation error, the instrumentation channel mismatch error, and the error caused by ambient noise, are studied systematically.

文中基于声信号的空间互谱分析，给出了声强向量阵的定向原理，并系统分析了其定向误差，包括有限差分误差、通道失配误差和环境噪声引起的误差。

The method transfers the observed data from space domain to 2-D space-time domain by exploiting the cross-correlation of the array outputs,and a large amount of virtual elements are generated through space-time processing.Therefore the constraint over the array configuration and the element identity can be significantly weakened,which means the matching subarray is no longer needed and the advantage of the traditional DOA matrix method,such as automatical parameter alignment and no need of 2-D search,is still available.

该方法在保持原DOA矩阵方法无需二维谱峰搜索和参数配对等优点的基础上，利用阵元输出之间的互相关关系将空域的阵列观测数据变换到时空域，通过空时二维处理在时空域中衍生出大量虚拟阵元，从而大大减弱了传统方法中对阵列结构、排布方式和阵元一致性的约束，不需要匹配子阵，无冗余阵元与孔径损失，并适用于阵元排列不规则的阵列。

A series of theoretical and experimental studies on the microstrip patch antennas with dielectric superstrates is carried out systematically. Firstly, a comprehensive survey of the microstrip antenna technology and its theories are presented. Then, two analysis techniques, named as the spectral domain Green's function method and the spectral domain integral equation method are developed. The SDGF method is a simplified analysis technique, which takes advantage of the spectral domain immittance approach to find the dyadic Green's function for the stratified media, and obtains the complete closed-form formulas for radiation patterns, directivity, efficiency, gain etc. Some interesting calculated results are presented. The SDIE method is capable of determining resonant frequency, radiation characteristics, input impedance etc, for the covered microstrip patch antennas. Comparing with other full-wave analyses it reduced computation and mathematical labour remarkably. The singularities near the pole location of the surface-wave modes and the difficulty of the integral computation over infinite range of oscillating integrands are dealt with actively and documented well. Results predicted by the SDIE method agree extremely well with our experimental results for resonant frequencies of various superstrates. The superstrate effects on impedance and radiation characteristics also have been investigated experimentally so that the gap due to lack of measured data and computed results for multi-layered superstrate has been filled to some degrees and two useful observations have been achieved for weakening the resonant frequency shift and optimizing the microstrip antenna gain. As a meaningful application, the design and analysis of a 4×4 patch array are introduced.

实用微带天线普遍加介质覆盖层来防护热，物理损伤和环境影响，也可能在飞行或严酷气候条件下自然形成覆盖层本论文对带介质覆盖层的微带贴片天线系统地作了一系列理论和实验研究首先，对微带天线技术和理论作了全面的综述然后，发展了两种分析方法，称为谱域格林函数法和谱域积分方程法SDGF法是一种简化的分析技术，它利用谱域导抗法来求得分层媒质的并矢格林函数，并得出方向图、方向性系数、增益等参数的完整的闭式公式，给出了一些令人感兴趣的计算结果SDIE法能确定介质覆盖微带天线的谐振频率、辐射特性和输入阻抗等与其它全波分析方法相比，它明显减小了计算量和数学工作量已有效地处理了表面波模极点附近的奇异性和对振荡的被积函数的无限区间积分计算的困难对于不同覆盖层情况下的谐振频率，由SDIE法所预示的结果与我们的实验结果吻合得很好对于覆盖层对阻抗和辐射特性的影响也已作了实验研究这在某种程度上填补了缺少实验数据和计算结果之间的间隙，并得出了缓解谐振频率偏移和优化天线增益的两点有用的结论作为有意义的应用，介绍了一个4×4元矩形贴片天线阵的设计和分析。

Results reveal that the spatial correlation properties of MIMO channel are dependent on the PAS, the antenna pattern and the geometric configuration of the array. When the PASs at the base station and the mobile station are independent, the spatial correlation matrix of the MIMO channel is the Kronecker product of the spatial correlation matrix at the BS and the MS. The temporal correlation properties of the MIMO channel are determined by the PAS at the MS, antenna pattern and the traveling speed of the MS. Based on the analysis of the physical essence, the temporal correlation properties are equivalent to the spatial correlation properties at the MS. The joint spatio-temporal correlation properties at the BS and the MS are quite different. When the PASs at the BS and the MS are independent, the spatial correlation at the BS is independent on the temporal correlation, but this is not true for the spatial correlation at the MS.

分析与计算的结果表明，MIMO信道的空间相关特性由角度谱、阵元的方向图、阵元间距以及阵列几何结构决定，并且当发射端与接收端的空间统计特性相互独立时，MIMO信道的空间相关矩阵可以表示为发射阵列空间相关矩阵与接收阵列空间相关矩阵的Kronecker乘积：信道的时间相关仅与MS端的角度谱、阵元方向图以及MS的运动速度有关，通过对信道时间相关的物理本质的研究，说明了时间相关与MS端空间相关的等价性；MIMO信道的空-时联合相关特性在BS端和MS端具有不同的特点，当发射端与接收端的空间统计特性相互独立时，BS端的空间相关与时间相关是独立的，而由于信道的时间相关与MS端的空间相关具有相同的物理本质，MS端的空间相关与时间相关不是独立的。

In this paper, firstly the differences between cylindrical array and uniform planar array are discussed in terms of eigenvalue distribution of the clutter covariance matrix and clutter distribution at range, and the conclusion of space-time clutter spectrum's nonhomogeneity at range for airborne radar with cylindrical array antennas is gained.

该文首先从圆柱型阵机载雷达杂波协方差矩阵特征值分布和杂波功率谱距离向分布两个方面分析了圆柱型阵列与均匀平面阵列之间的区别，得到杂波功率谱随距离变化的结论。

Thereinto, for the spectral decomposition estimate of the covariance matrix ,we can gain the risk functions under some losses.

其中，对于观测向量协方差阵的谱分解估计，我们很容易得到它在一些损失下的风险函数。

Our results improve the former results. For periodic Jacobi matrix, some new spectral properties of periodic Jacobi matrix are given by studying the relationship of the eigenvalues of periodic Jacobi matrix and its n—1 principal submatrix. Applying these spectral properties, we present a necessary and sufficient condition for the solvability of an inverse problem of periodic Jacobi matrices and discuss the number and the relationship of its solutions. Furthermore, we propose a new algorithm to construct its solution and compare it with the former algorithms. As this inverse problem of periodic Jacobi matrix usually has multiple solutions as many other eigenvalue inverse problems, we study the uniqueness of this problem. And a necessary and sufficient condition is given to ensure its uniqueness, under which an algorithm is presented and the stability analysis is also given. Finally, we put forward a new inverse problem for periodic Jacobi matrix which has not been solved.

对周期Jacobi矩阵特征值反问题，通过研究周期Jacobi矩阵与其n-1阶主子阵特征值的关系，给出了周期Jacobi矩阵的一些新的谱性质；利用这些谱性质，研究了一类周期Jacobi矩阵特征值反问题，用新的方法推导出了该类特征值反问题有解的充分必要条件，并讨论了解的个数以及解与解之间的关系；此外，提出了一种新的构造周期Jacobi矩阵反问题解的数值算法，并与前人的算法做了一定比较；由于周期Jacobi矩阵特征值反问题和其他很多特征值反问题一样往往存在多个解，本论文给出了周期Jacobi矩阵反问题解唯一的充要条件，并发现周期Jacobi矩阵特征值反问题的解唯一当且仅当构造的矩阵满足一定的条件；在解唯一的情况下，给出了构造唯一解的数值算法，并做了相应的稳定性分析；最后，提出了一类新的有待于解决的周期Jacobi矩阵特征值反问题。

By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.

在窄带条件下，GSC－SSF方法还可以提高阵列的虚拟孔径，从而提高估计的性能；可以证明，Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似； 3、提出了二维GSC－SSF方法和宽带谱相关DOA矩阵方法，利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题，并具有阵元数少、计算量较小的特点； 4、提出了时频子空间拟合和宽带时频DOA估计算法，将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中，利用时变滤波实现信号选择性测向和干扰抑制，特别适合于谱时变信号；可以证明传统特征结构法可看作是时频子空间拟合方法的特例； 5、提出了多用户环境下阵列响应的估计方法——CARE方法，该方法对信号结构和传播参数（主要是散射源分布与角度散布）的约束较少，适用于各种几何结构的阵列甚至未校准的阵列，能够直接得到阵列响应的闭式解，因此计算量小、稳健性好，不存在收敛问题； 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案，通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束，并保证各波束内的用户信号各不相同且相互干扰最小；其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点，其有效性已得到外场实测数据的证实。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。