This document discusses the electromagnetic modeling of large planar arrays using the Scale Changing Technique (SCT). SCT decomposes planar structures into hierarchical scales to reduce computational requirements. It expresses fields on orthogonal modes and computes scale-changing networks between domains to model coupling. The document presents applications of SCT to modeling infinite and finite reflectarrays, characterizing coupling in non-uniform arrays, and simulating 2D arrays under plane wave and horn excitation. SCT was shown to efficiently model multiscale arrays and characterize coupling while avoiding issues of conventional full-wave solvers.
NON-SPLIT PERFECTLY MATCHED LAYER BOUNDARY CONDITIONS FOR NUMERICAL SOLUTION ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The
point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Non-split Perfectly Matched Layer Boundary Conditions for Numerical Solution ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Modeling the transport of charge carriers in the active devices diode submicr...IJERA Editor
A Monte Carlo simulation program was developed to simulate the movement of electrons in a submicron GaInP diode three dimensional (3D) with 0.1 microns-long active layer. The algorithm couples a standard Monte Carlo particle simulator for the Boltzmann equation with a 3D Poisson solver. Thus a series of hits for a specific MC submicron diode (GaInP), with an active layer (n = 2x1015cm-3) of length 0.1μm surrounded by two regions doped with n = 5x1017cm-3, are presented. The lattice temperature is 300K and the anode voltage Va is 1V. The analysis also showed that the average drift velocity to the electrons in the channel is about 5x106 cm/sec
Designing of an Energy-Efficient Nanoelectronics Architecture for Binary Comp...VIT-AP University
Quantum-dot cellular automata is a nanoscale computation circuit design approach which computes bits via charges
among quantum-dot in the quantum cell of QCA. This technology has promises the feature of energy efficient and high
density in the era of high-speed nanotechnology. This article contributes a new nanoscale design of binary comparator
with less latency, area, and clock utilized. The proposed comparator architecture is robust and enjoys wire crossing
without any crossover, which needs only normal and rotated cells. All the simulation results and calculated parameters
are based on the QCADesigner tool. QCAPro tool based approach has been used to perform the energy dissipation
estimation of the new comparator architecture. A better primitives results as compared to state-of-art technology has
been achieved and good contribution in this area.
Internal multiple attenuation using inverse scattering: Results from prestack...Arthur Weglein
The attenuation of internal multiples in a multidimensional
earth is an important and longstanding problem in exploration
seismics. In this paper we report the results of applying
an attenuation algorithm based on the inverse scattering
series to synthetic prestack data sets generated in on
and two dimensional earth models. The attenuation algorithm
requires no information about the subsurface structure
or the velocity field. However, detailed information about
the source wavelet is a prerequisite. An attractive feature of:
the attenuation algorithm is the preservation of the amplitude
(and phase) of primary events in the data; thus allowing for
subsequent AVO and other true amplitude processing.
Modeling of solar array and analyze the current transientEditor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
This paper investigates about the possibility to reduce power consumption in Neural Network using approximated computing techniques. Authors compare a traditional fixed-point neuron with an approximated neuron composed of approximated multipliers and adder. Experiments show that in the proposed case of study (a wine classifier) the approximated neuron allows to save up to the 43% of the area, a power consumption saving of 35% and an improvement in the maximum clock frequency of 20%.
NON-SPLIT PERFECTLY MATCHED LAYER BOUNDARY CONDITIONS FOR NUMERICAL SOLUTION ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The
point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Non-split Perfectly Matched Layer Boundary Conditions for Numerical Solution ...ijeljournal
This paper developed a non - split perfectly matched layer (PML) boundary condition (BC) for Finite Difference Time Domain (FDTD) simulation of electromagnetic wave propagation in 2D structure. The point source for electric field has been exploited for propagation of electromagnetic field through 2D structures to validate developed approach. The identity of resulted field distribution to that obtained for split PML BC have been demonstrated.
Modeling the transport of charge carriers in the active devices diode submicr...IJERA Editor
A Monte Carlo simulation program was developed to simulate the movement of electrons in a submicron GaInP diode three dimensional (3D) with 0.1 microns-long active layer. The algorithm couples a standard Monte Carlo particle simulator for the Boltzmann equation with a 3D Poisson solver. Thus a series of hits for a specific MC submicron diode (GaInP), with an active layer (n = 2x1015cm-3) of length 0.1μm surrounded by two regions doped with n = 5x1017cm-3, are presented. The lattice temperature is 300K and the anode voltage Va is 1V. The analysis also showed that the average drift velocity to the electrons in the channel is about 5x106 cm/sec
Designing of an Energy-Efficient Nanoelectronics Architecture for Binary Comp...VIT-AP University
Quantum-dot cellular automata is a nanoscale computation circuit design approach which computes bits via charges
among quantum-dot in the quantum cell of QCA. This technology has promises the feature of energy efficient and high
density in the era of high-speed nanotechnology. This article contributes a new nanoscale design of binary comparator
with less latency, area, and clock utilized. The proposed comparator architecture is robust and enjoys wire crossing
without any crossover, which needs only normal and rotated cells. All the simulation results and calculated parameters
are based on the QCADesigner tool. QCAPro tool based approach has been used to perform the energy dissipation
estimation of the new comparator architecture. A better primitives results as compared to state-of-art technology has
been achieved and good contribution in this area.
Internal multiple attenuation using inverse scattering: Results from prestack...Arthur Weglein
The attenuation of internal multiples in a multidimensional
earth is an important and longstanding problem in exploration
seismics. In this paper we report the results of applying
an attenuation algorithm based on the inverse scattering
series to synthetic prestack data sets generated in on
and two dimensional earth models. The attenuation algorithm
requires no information about the subsurface structure
or the velocity field. However, detailed information about
the source wavelet is a prerequisite. An attractive feature of:
the attenuation algorithm is the preservation of the amplitude
(and phase) of primary events in the data; thus allowing for
subsequent AVO and other true amplitude processing.
Modeling of solar array and analyze the current transientEditor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
This paper investigates about the possibility to reduce power consumption in Neural Network using approximated computing techniques. Authors compare a traditional fixed-point neuron with an approximated neuron composed of approximated multipliers and adder. Experiments show that in the proposed case of study (a wine classifier) the approximated neuron allows to save up to the 43% of the area, a power consumption saving of 35% and an improvement in the maximum clock frequency of 20%.
Design of a Selective Filter based on 2D Photonic Crystals Materials IJECEIAES
Two dimensional finite differences temporal domain (2D-FDTD) numerical simulations are performed in cartesian coordinate system to determine the dispersion diagrams of transverse electric (TE) of a two-dimension photonic crystal (PC) with triangular lattice. The aim of this work is to design a filter with maximum spectral response close to the frequency 1.55 μm. To achieve this frequency, selective filters PC are formed by combination of three waveguides W 1 K A wherein the air holes have of different normalized radii respectively r 1 /a=0.44, r 2 /a=0.288 and r /a= 0.3292 (a: is the periodicity of the lattice with value 0.48 μm). Best response is obtained when we insert three small cylindrical cavities (with normalized radius of 0.17) between the two half-planes of photonic crystal strong lateral confinement.
Radiation patterns account of a circular microstrip antenna loaded two annularwailGodaymi1
In this paper, theoretical study of circular microstrip antenna loaded two annular (CMSAL2AR) and calculation
of the radiation pattern using principle equivalence with moment of method formulation of electromagnetic
radiation in this these based on the bodies of revolution (BoR), which are generated by revolution a planar curve
about an axis called axis of symmetry to solving the electric fields integral equation (EFIE) and magnetic field
integral equation (MFIE). To find an unknown electric current density on the conductor surface ,and both
unknowns electric and magnetic density current on the dielectric surface which are responsible for the
generation of far fields radiation in the space for the components (Eθ ,Eφ) ,the surface currents was represented
by a set of basis functions that give the Fourier series because the body has a circular symmetry property and
then select a set of weighted functions to find a linear system by using Galerkin method which requires that the
weighted functions are equal to the complex conjugate of the current ( ) * W = J .from radiation pattern
calculated the Directive gain can be utilized to the directive gain increased to (G= 21.30 dB) when
( 0.015λ 1 = g R ) for the ratio of (Rab= 5.5), and bandwidth has been better (BW%= 19.9%) when
( 0.01λ 1 = g R ) for the ratio (Rab= 6.5) .
Artificial Neural Network in the Design of Rectangular Microstrip Antennaaciijournal
A simple design to compute accurate resonant frequencies and the electric fields of rectangular microstrip
antennas using artificial neural networks (ANN) is proposed. The ANN is developed to calculate the
frequency and antenna's field. ANN is designed using multilayer perceptron networks (MLP). The results
that were obtained accord the trained and tested data of ANN models. As a result, the ANN model is
presented as a substitutional method to the detailed electromagnetic design of rectangular microstrip
antenna.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Implementation of Digital Beamforming Technique for Linear Antenna Arraysijsrd.com
A digital Beamforming technique used for increased channel capacity and also increased signal to noise and interference ratio. In smart antenna, different type of radiation pattern of an antenna can be changed either by selecting appropriate weights or by changing the array geometry. This paper presented based on auxiliary phase algorithm by using this algorithm in linear antenna array determine the array pattern approximating the auxiliary function in both amplitude and phase. Cost function involving auxiliary function and array pattern is minimized by modifying the pattern.
EFFECTIVE PEEC MODELING OF TRANSMISSION LINES STRUCTURES USING A SELECTIVE ME...EEIJ journal
The transmission lines structures are quite common in the system of electromagnetic compatibility (EMC)
analysis. The increasing complexities of physical structures make electromagnetic modeling an
increasingly tough task, and computational efficiency is desirable. In this paper, a novel selective mesh
approach is presented for partial element equivalent circuit (PEEC) modeling where intense coupling parts
are meshed while the remaining parts are eliminated. With the proposed approach, the meshed ground
plane is dependent on the length and height of the above transmission lines. Relevant compact formulae for
determining mesh boundaries are deduced, and a procedure of general mesh generation is also given. A
numerical example is presented, and a validation check is accomplished, showing that the approach leads
to a significant reduction in unknowns and thus computation time and consumed memories, while
preserving the sufficient precision. This approach is especially useful for modeling the electromagnetic
coupling of transmission lines and reference ground, and it may also be beneficial for other equivalent
circuit modeling techniques.
Design and manufacturing of iris waveguide filters for satellite communicationTELKOMNIKA JOURNAL
We propose in this paper, two bandpass filters in waveguide technology having rectangular symmetrical discontinuities with a half-radius r, designed and operating respectively in the X-Band (9-11.5) GHz and C-Band (3.5-5.5) GHz. These filters consists of eight irises placed symmetrically respectively on standard rectangular waveguides WR90 and WR229 in which resonant irises are inserted. These irises are used to couple the sections very strongly in this filter, which allows the bandwidth to be increased and the matching to be controlled. The comparison between the numerical and electromagnetic results, which we obtained for the filters, constitutes a means of validation of computer simulation technology (CST) environment and Mician for the design of the other circuit elements in the various frequency bands. We observed excellent consistency between the simulation curves and those of the measurements. The results obtained are promising and pave the way for the use of these structures in the fields of telecommunications.
1. Electromagnetic Modeling of Large and Non-uniform Planar Array Structures using Scale Changing Technique (SCT) Presented by: Aamir RASHID Thesis Adviser: M. HervéAubert 1
2. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 2
3. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 3
12. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 5
13. Scale Changing Technique W1 W3 W0 Reflectarray Phase-shifter cell RF-MEMS switch W2 W4 Slot loaded by RF-MEMS switches Region below the switch 100 10-1 10-2 10-3 10-4 10-5 Surface of Wi / Surface of W0 RF-MEMS controlled Reflectarray – An example of a multiscale structure 10-6 Simulation of such structures with conventional techniques a Nightmare!! 6
14. Scale Changing Technique Decomposition of the planar surface ------- by introducing artificial boundary conditions Definition of tangential electromagnetic fields on orthonormal modal basis Determination of appropriate number of modes Computation of Scale-changing Networks (SCN) Cascade of all SCNs 7
15. Scale Changing Technique W3 W2 W4 Partitioning of the Discontinuity Plane W1 [Ref] E.Perret et al, “Scale-changing technique for the electromagnetic modeling of MEMS-controlled planar phase-shifters”, IEEE Transactions on Microwave Theory and Techniques, Vol.54, No.9, September 2006, Pages: 3594-3601. 8
24. EM coupling between parent domain and daughter subdomains is largely due to lower order modes ---- active modes
25. Appropriate number of active and passive modes need to be determined --- convergence study
26. EM coupling between a domain at scale ‘s’ and its subdomains at scale ‘s-1’ is represented by a Scale Changing Network9
27. Scale Changing Technique Scale Changing Network (SCN) A multiport network where the ports represent active modes Models EM coupling between successive scales Computation of all SCNs mutually independent --- PARALLEL PROCESSING 10
29. Scale Changing Technique Structures already simulated using SCT MEMS controlled Reflector cell Active Patch Antenna [Ref] E.Perret et al, “Scale-changing technique for the computation of the input impedance of active patch antennas”, IEEE Antennas and Wireless Propagation Letters, Vol.4, 2005. Multi-frequency Selective surfaces Prefractal Multi-band scatterer [Ref] D.Voyer et al, “Scale-changing technique for the electromagnetic modeling of planar self-similar structures”, IEEE Transactions on Antennas and Propagation, Vol.54, No.10, October 2006. 12
30. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 13
31. Infinite Reflectarray Modeling Planar Reflector Cell under infinite array conditions y Floquet modal expansion to simulate infinite array conditions kinc Plane-wave Excitation (Oblique Incidence) θ φ b2 b1 b0 Nine geometric configurations simulated varying dimensions b1 and a2 a2 z a1 Objective: To find the phase of reflection coefficients for TE00 and TM00 modes a0 Periodic BC Magnetic BC Electric BC a0=15mm b0=15mm Dielectric thickness = 4mm Dielectric=Air a1=12mm b2=1mm b1 and a2variable 14
32. Infinite Reflectarray Modeling Application of Scale Changing Technique (SCT) Partitioning of planar geometry at three scale-levels Cascade of SCNs 15
33. Infinite Reflectarray Modeling Convergence Study (Normal Incidence) Convergence curves between modes in domains D1(2) and D1(3) (discontinuity domain) Convergence curves between active modes in domains D1(2) and D1(1) (slot domain) Modes for convergence 2500 [D1(3)] 600 [D1(2)] 80 [D1(1)] 16
34. Infinite Reflectarray Modeling Numerical Results (Normal Incidence) Phase results for the reflection coefficient of TM00 mode Convergence study performed at the centre frequency of 12.1GHz for each case ____ SCT x xx HFSS 17
35. Infinite Reflectarray Modeling Numerical Results (Oblique Incidence) at 12.1 GHz (φinc = 0⁰) Phase S11 (Degrees) SCT solid lines HFSS broken lines Variation in the phase results of the TM00 mode with the change in the incidence angle (θ) 18 Phase S22(Degrees) Variation in the phase results of the TE00mode with the change in the incidence angle (θ)
36. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 19
42. Electromagnetic Coupling Characterization Bifurcation Scale Changing Network Multiport Representation of Bifurcation SCN (Characterized by an impedance or admittance matrix ) Equivalent Electric Network (for only TEM excitation in each domain) 21
44. Electromagnetic Coupling Characterization Scattering from two planar half-wave dipoles RCS ratio in the absence of mutual coupling For separation D >> λ RCS Ratio λ 23
45. Electromagnetic Coupling Characterization Electromagnetic coupling modeled by Bifurcation SCN IE3D SCT |Er| in the absence of mutual coupling (IE3D SCT) [Ref] A.Rashid, H.Aubert , “Modeling of Electromagnetic Coupling in Finite Arrays Using Scale-changing Technique”, Progress In Electromagnetics Research Symposium (PIERS), 5-8 July 2010, Cambridge, USA. 24
46. Modeling Linear Arrays Modeling of a non-uniform linear (1-D) array of metallic stripes A non-uniform array of lossless metallic strips A unit-cell of the array Dimensions: a=10 mm b=9mm x=2mm Freq=5 GHz Partitioning process of an eight cell array 25
47. Modeling Linear Arrays Modeling of a non-uniform linear (1-D) array of metallic stripes Modeling of entire array by an iterative cascade of Bifurcation SCNs 26
48. Modeling Linear Arrays Modeling of a non-uniform linear (1-D) array of metallic stripes 27
49. Modeling Linear Arrays Modeling of a non-uniform linear (1-D) array of metallic stripes Execution Time (Normalized) Iteration = Number of Bifurcation SCNs used Array size (no of unit-cells) = 2^(Iteration) 1. [Ref] A.Rashid, H.Aubert, H.Legay “ Modélisation Electromagnétique d’un Réseau Fini et Non-Uniforme par la Technique par Changements d’Echelle”, JNM 2009, Grenoble 28
50. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 29
51. Modeling 2-D Planar Arrays Bifurcation Scale Changing Network in 2-D Partitioning of 2-D planar array Phase results for the reflection coefficient of TM00 mode Cascade of SCNs 30
52. Modeling 2-D Planar Arrays Formulation of the Scattering Problem Surface Equation for electromagnetic scattering from a planar surface When an equivalent current is assumed at the whole discontinuity plane In spectral domain Using Galerkin’s method 31
60. Modeling 2-D Planar Arrays Execution Times to compute surface impedance of the array 8x8 uniform array 8x8 non-uniform array 39
61. Presentation Plan Motivation Scale Changing Technique (SCT) Modeling of a Planar Reflector cell Characterization of Electromagnetic Coupling in non-uniform array Scattering from 2-D Planar Arrays Conclusions and Perspectives 40
62.
63. SCT models mutual coupling effects between the elements of non-uniform arrays
64. The unique formulation avoids the direct computation of large structures with high aspect ratios – thus prevents numerical and convergence errors
65. Inherent modular nature of SCT allows the parallel execution of SCNs allowing execution times to increase linearly with the exponential increase in array size
66. In case of a modification in geometry at a given scale only two SCNs need to be recalculated ---- an essential feature for a good PARAMETRIC and OPTIMIZATION TOOL 41
71. Publications A. Rashid et al, "Modeling of Infinite Passive Planar Structures using Scale-Changing Technique"IEEE-APS July 5-11, 2008, SanDiego, USA. A. Rashid et al, "Modélisation Electromagnétique d’un Réseau Fini et Non-Uniforme par la Technique par Changements d’Echelle"JNM 2009, Grenoble, France. A. Rashid et al, "Modeling of finite and non-uniform patch arrays using scale-changing technnique "IEEE-APS June 1-5, 2009, Charleston, USA. A. Rashid et al, "Scale-Changing Technique for the numerical modeling of large finite non-uniform array structures " PIERS, 2009, Moscow, Russia. E.B.Tchikaya et al, "Multi-scale Approach for the Electromagnetic Modeling of Metallic FSS Grids of Finite Thickness with Non-uniform Cells "APMC, 2009, Singapore. F. Khalil et al, "Application of scale changing technique-grid computing to the electromagnetic simulation of reflectarrays "IEEE-APS June 1-5, 2009, Charleston, USA. 44