Analysis and suppression of SSN noise coupling between power/ground plane cavities through cutouts in multilayer packages and PCBs

The authors introduced a model of simultaneous switching noise (SSN) coupling between the power/ground plane cavities through cutouts in high-speed and high-density multilayer pack-ages and printed circuit boards (PCBs). Usually, the cutouts are used in multilayer plane structures to isolate the SSN of noisy digital circuits from sensitive analog circuits or to provide multiple voltage levels. The noise-coupling model is expressed in terms of the transfer impedance. The proposed modeling and analysis results are compared with measured data up to 10 GHz to demonstrate the validity of the model. It is demonstrated that the cutout is the major gate for SSN coupling between the plane cavities, and that substantial SSN coupling occurs between the plane cavities through the cutout at the resonant frequencies of the plane cavities. The coupling mechanism and characteristics of the noise coupling, from which a method of suppression of the SSN coupling evaluated was also analyzed and discussed. Proper positioning of the cutout and the devices at each plane cavity achieves significant noise suppression at certain resonant frequencies. The suggested suppression method of the SSN coupling was successfully proved by frequency domain measurement and time domain analysis.     

A Generalized 2-D Multiport Model for Planar Circuits With Slots in Ground Plane

A new approach for multiport network modeling (MNM) of multilayer planar circuits coupled through slots in ground plane is introduced. Generalized network formulation for aperture problems is combined with Okoshi's model for planar circuits to obtain a unified circuit model for two irregularly shaped planar circuits coupled through a slot of arbitrary shape in their common ground plane. The methodology, which can be generalized to structures having more than two layers, is described by applying the method to a two-layer structure. Results for several sample structures will also be presented     

Modeling and measurement of simultaneous switching noise coupling through signal via transition

The signal via is a heavily utilized interconnection structure in high-density System-on-Package (SoP) substrates and printed circuit boards (PCBs). Vias facilitate complicated routings in these multilayer structures. Significant simultaneous switching noise (SSN) coupling occurs through the signal via transition when the signal via suffers return current interruption caused by reference plane exchange. The coupled SSN decreases noise and timing margins of digital and analog circuits, resulting in reduction of achievable jitter performance, bit error ratio (BER), and system reliability. We introduce a modeling method to estimate SSN coupling based on a balanced transmission line matrix (TLM) method. The proposed modeling method is successfully verified by a series of time-domain and frequency-domain measurements of several via transition structures. First, it is clearly verified that SSN coupling causes considerable clock waveform distortion, increases jitter and noise, and reduces margins in pseudorandom bit sequence (PRBS) eye patterns. We also note that the major frequency spectrum component of the coupled noise is one of the plane pair resonance frequencies in the PCB power/ground pair. Furthermore, we demonstrate that the amount of SSN noise coupling is strongly dependent not only on the position of the signal via, but also on the layer configuration of the multilayer PCB. Finally, we have successfully proposed and confirmed a design methodology to minimize the SSN coupling based on an optimal via positioning approach.     

Analysis of multilayer printed arrays by a modular approach basedon the generalized scattering matrix

In this paper, a modular technique is used to treat infinite multilayer printed arrays with apertures and patches of irregular shapes. Each array layer is characterized by a generalized scattering matrix (GSM) from which the overall GSM of the multilayer structure is computed. The excitation of each element is modeled as a transition from the microstrip line to an aperture in the ground plane. The GSM of this transition is computed using the reciprocity theorem and spectral domain moment method. Several arrays have been analyzed by the proposed technique and the numerical results are in good agreement with other theoretical and experimental data     

New multilayer planar transmission lines for microwave andmillimeter-wave integrated circuits

New types of planar transmission lines employing multilayer structures are proposed for possible applications in microwave and millimeter-wave integrated circuits. Detailed investigations are presented through numerical results calculated using the spectral domain technique. The newly proposed transmission lines have many attractive features such as a large impedance range, flexibility and ability to realize complicated, densely packed integrated circuits, as well as miniaturization through the use of thin dielectric layers. Additionally, they possess all of the inherent advantages of the CPW and microstrip line. Their use in microwave circuits is exemplified through a low-pass filter realized using the new slot-coplanar lines with less than 0.5-dB insertion loss and better than 20-dB return loss. The filter's measured and calculated performances also agree well     

Hybrid analytical modeling of noise coupling to signal traces in a power bus with embedded film capacitor

An accurate hybrid analytical method is proposed to determine the coupling of switching noise to signal traces in a multilayer power bus with embedded film capacitor. We used the induction equivalent theorem to derive the solution of noise coupling and the segmentation method to calculate the electric field of the noise in a power bus. The proposed method was verified by measurements of impedance parameters in the frequency domain.     

Spectral domain analysis of eigenmodes in a shielded multilayer coplanar waveguide for microwave and millimeter-wave integrated circuits

Coplanar waveguide has found increasing use in microwave and millimeter-wave integrated circuits, and a knowledge of its eigenmodes is very useful for circuit design. In this paper, we determine the dispersion properties of the eigenmodes in a shielded multilayer coplanar waveguide using the spectral domain approach. Numerical results of the propagation constants for different combinations of dielectric materials are presented to illustrate the behaviors of the eigenmodes.     

Full-wave modeling of coplanar waveguide discontinuities withfinite conductor thickness

An extended version of the spectral domain approach (SDA) is developed to analyze discontinuities in open coplanar waveguide with finite metallization thickness. By making use of the exact Green's function in the spectral domain, the effects of surface wave and radiation phenomena are accurately accounted for. Both longitudinal and transverse components of the aperture electric fields are used in the analysis to allow modelling of structures with large transverse dimensions at high frequencies. The procedure also includes mode conversion near the discontinuities. As an illustration of the method, analytical steps and computed scattering parameters of the coplanar waveguide short-circuits and transitions are provided and compared against measured data     

Feature fusion via dual-resolution compressive measurement matrix analysis for spectral image classification

In the compressive spectral imaging (CSI) framework, different architectures have been proposed to recover high-resolution spectral images from compressive measurements. Since CSI architectures compactly capture the relevant information of the spectral image, various methods that extract classification features from compressive samples have been recently proposed. However, these techniques require a feature extraction procedure that reorders measurements using the information embedded in the coded aperture patterns. In this paper, a method that fuses features directly from dual-resolution compressive measurements is proposed for spectral image classification. More precisely, the fusion method is formulated as an inverse problem that estimates high-spatial-resolution and low-dimensional feature bands from compressive measurements. To this end, the decimation matrices that describe the compressive measurements as degraded versions of the fused features are mathematically modeled using the information embedded in the coded aperture patterns. Furthermore, we include both a sparsity-promoting and a total-variation (TV) regularization terms to the fusion problem in order to consider the correlations between neighbor pixels, and therefore, improve the accuracy of pixel-based classifiers. To solve the fusion problem, we describe an algorithm based on the accelerated variant of the alternating direction method of multipliers (accelerated-ADMM). Additionally, a classification approach that includes the developed fusion method and a multilayer neural network is introduced. Finally, the proposed approach is evaluated on three remote sensing spectral images and a set of compressive measurements captured in the laboratory. Extensive simulations show that the proposed classification approach outperforms other approaches under various performance metrics.     

Artificial Neural Network Models for the Crossover Discontinuities in Stripline Circuits

Crossover discontinuities between two adjacent orthogonal signal layers often appear in many stripline circuits, such as the multilayer microwave monolithic ICs and the interconnect systems in high-speed digital circuits. In this paper , a multilayer perceptron neural network(MLPNN) is used to model the electrical properties of the crossover discontinuities in stripline circuits. The MLPNN is electromagnetically developed with a set of training data that are produced by the full-wave finite-difference time-domain method. The full-factor design of experiments is used to determine the size of the training data.     

Hankel transform-domain analysis of scattered fields in multilayer planar waveguides and lasers with circular gratings

Radiation patterns of scattered fields with arbitrary azimuthal orders in multilayer planar waveguides and laser cavities with circularly symmetric gratings are formulated based on the volume current method. Full-wave Green's function analysis based on the integral transform method lies at the heart of this approach. Unlike the conventional approach, the dyadic Green's function relates some auxiliary fields to some auxiliary sources in the spectral domain. These auxiliary functions are defined to facilitate the spectral domain formulation in the cylindrical coordinate system and the use of transfer matrix method for obtaining a closed-form solution of the spectral Green's function in multilayer planar structures. More importantly, it is shown that the far-field pattern of the scattered field can be expressed directly in terms of the auxiliary fields in the Hankel transform domain.     

均匀平面阵下的二维DOA估计与互耦自校正

针对存在互耦效应时均匀平面阵的测向鲁棒性问题,提出了一种基于秩损准则的互耦自校正算法。根据对互耦效应的先验知识,提出的算法只需将受互耦扰动的阵列响应在变换域中重新排列,便可在后续处理中屏蔽掉互耦效应的不利影响,同时也避免了现有工作中存在的阵列孔径损失问题。借助秩损估计原理,在变换域中设计了一种巧妙的计算步骤,使得方位估计的降维操作得以实现;并且,后续还可通过特征分解法得到更精确的互耦系数估计,以进行阵列误差自校正。与现有的研究工作相比,所提算法无论是在估计精度,还是在计算效率上均有着显著的性能优势。     

Analysis of slow-wave transmission lines on multi-layeredsemiconductor structures including conductor loss

Metal lines on semiconductor devices and circuits sometimes show slow-wave phenomena. To determine signal transmission characteristics along the lines, the typical assumption that metal is perfectly conducting is not always valid. A simple and accurate means is used here to include metallic loss in spectral domain analysis of planar transmission lines built on multilayer semiconducting media. Experimental results with a modulation-doped field-effect transistor (MODFET) structure and comparison with the calculations are presented     

一个基于并行时域Diakoptics的离散格林函数的新算法

本文介绍一个计算系统离散格林函数的新方法－－并行时域Ｄｉａｋｏｐｔｉｃｓ法,将一个较简单的子域,用有时域差分法计算各子域的时域响应,用并行射ｉａｋｏｐｔｉｃｓ计算任意彼此相邻的两个子域间的电磁耦合,并最终得到整个系统的离散格林函数,与传统的模式匹配法和有限时域差分法（ＦＤＴＤ）比较,本方法可处理几何结构更为复杂的问题,并且具有较好的精度及计算效率。     

多层介质多导体系统的时域分析

本文给出了谱域法和频域波形迭代法相结合的分析多层介质多导体系统的时域响应算法，考虑了多导体系统中的色散、互耦效应。文章给出的计算结果验证了该方法的可靠性和适用范围。     

Calculation of characteristic impedance of planar structures using coupling and decoupling of hybrid modes in the spectral domain

A new techniue based on the spectral domain method for calculating the characteristic impedance of planar dispersive structures with multilayer dielectric substrates is presented. The coupling and decoupling of LSE and LSM modes are introduced so that the calculation of whole power in the considered structure bcomes very easy and fast. Numerical results are presented for some complex structures.     

A mixed spectral-domain approach for dispersion analysis ofsuspended planar transmission lines with pedestals

A mixed spectral-domain analysis is used to derive dispersion characteristics of domain modes in a class of planar transmission lines with a pedestal. Equivalent structures are constructed in which magnetic surface currents are identified as the unknowns at the aperture separating two different regions. Spectral dyadic Green's functions are derived for these structures using the spectral-domain immittance approach. The characteristic equations resulting from the application of the spectral Galerkin method involve mixing two different spectral domains, which exist on the two sides of the pedestal support. The present method allows one to retain the simplicity and numerical efficiency of the conventional spectral-domain immittance approach, which cannot be applied directly to the present structures. Numerical data are provided for the dispersion characteristics of dominant modes in a pedestal-supported stripline and finline     

Scalarization of dyadic spectral Green's functions and networkformalism for three-dimensional full-wave analysis of planar lines andantennas

A novel and systematic method is presented for the complete determination of dyadic spectral Green's functions directly from Maxwell's equations. With the use of generalized scalarizations developed in this paper, four general and concise expressions for the spectral Green's functions for one-dimensionally inhomogeneous multilayer structures, excited by three-dimensional electric and magnetic current sources, are given in terms of modal amplitudes together with appropriate explicit singular terms at the source region. It is shown that Maxwell's equations in spectral-domain can be reduced, by using dyadic spectral eigenfunctions, to two sets of z-dependent inhomogeneous transmission-line equations for the modal amplitudes. One set of the transmission-line equations are due to the transverse current sources and the other set due to the vertical current sources. Utilizing these equations, network schematizations of the excitation, transmission and reflection processes of three-dimensional electromagnetic waves in one-dimensionally inhomogeneous multilayer structures are achieved in a full-wave manner. The determination of the spectral Green's functions becomes so simple that it is accomplished by the investigation of voltages and currents on the derived equivalent circuits. Examples of singleand multilayer structures are used to validate the general expressions and the equivalent circuits     

The Application of Lumped Element Equivalent Circuits Approach to the Design of Single-Port Microstrip Antennas

A simple method for inverting negative resistances of nonphysical circuits generated from approximating rational functions through vector fitting is proposed. This technique is applied to three resonant antenna structures. The challenge of applying this method to these structures lies in the accurate modeling of the ways in which the different resonant modes are excited, some via coaxially feeding a rectangular patch along the diagonal, while others via capacitively coupling energy from the driven patch to a parasitic patch. The equivalent circuits of these designs produce scattering parameter results that are consistent with the fitted functions. This methodology of resistance invertibility is a great tool that can be used to model antenna designs with low order equivalent circuits, drastically reducing the design time. In addition, valuable information that could aid in the optimization of microstrip antennas can be quickly ascertained through these techniques.     

Analysis of asymmetrical multilayer ferrite-loaded finlines by theextended spectral domain approach

The spectral domain approach is extended to analyze the nonreciprocal propagation characteristics of asymmetrical multilayer finlines containing magnetized ferrites. This extended method offers several advantages. It can be applied to nonuniform cross-section geometries, uses only one set of basis functions, and the dyadic Green's function is efficiently derived by a recursive algorithm. Fast convergence is obtained and the accuracy of the method is verified by comparison with available computed and measured data. In comparison with symmetrical structures, the additional design degree of freedom of the asymmetry can be used to obtain wider bandwidth and higher nonreciprocity. Of the various structures considered, a four-layer dual ferrite (DF) structure is seen to be the best choice for realization of nonreciprocal phase shifters with widest bandwidth