Engineering › Aerospace Engineering

Antenna Design and Optimization

Works Count: 49897

Wikipedia

Description

This cluster of papers focuses on the application of advanced optimization techniques such as Particle Swarm Optimization, Differential Evolution, and Genetic Algorithms to the design and synthesis of antenna arrays. The research covers various types of arrays including linear, planar, circular, and phased arrays, with an emphasis on achieving optimal performance in terms of sidelobe level suppression, null control, and beamforming.

Keywords

Antenna Arrays; Optimization; Particle Swarm Optimization; Differential Evolution; Genetic Algorithms; Sparse Arrays; Linear Array Synthesis; Time-Modulated Arrays; Phased Array Antennas; Pattern Synthesis

Software radio: a modern approach to radio engineering

2002-05-20

Jeffrey H. Reed

Software-based approaches enable engineers to build wireless system radios that are easier to manufacture, more flexible, and more cost-effective. Software Radio: A Modern Approach to Radio Engineering systematically reviews the … Software-based approaches enable engineers to build wireless system radios that are easier to manufacture, more flexible, and more cost-effective. Software Radio: A Modern Approach to Radio Engineering systematically reviews the techniques, challenges, and tradeoffs of DSP software radio design. Coverage includes constructing RF front-ends; using digital processing to overcome RF design problems; direct digital synthesis of modulated waveforms; A/D and D/A conversions; smart antennas; object-oriented software design; and choosing among DSP microprocessors, FPGAs, and ASICs. This is an excellent book for all RF and signal processing engineers building advanced wireless systems.

Microwave Horns and Feeds

1994-01-01

A.D. Olver , P.J.B. Clarricoats , A.A. Kishk +1 more

This book is devoted to describing the theory, design, performance and application of microwave horns and feeds for reflector. The first general treatment of feeds for reflector antennas, it describes … This book is devoted to describing the theory, design, performance and application of microwave horns and feeds for reflector. The first general treatment of feeds for reflector antennas, it describes design principles and methods of analysis.

Microwave Antenna Theory and Design

1984-01-01

Samuel Silver

* Chapter 1: Survey of microwave antenna design problems * Chapter 2: Circuit relations, reciprocity theorems * Chapter 3: Radiation from current distributions * Chapter 4: Wavefronts and rays * … * Chapter 1: Survey of microwave antenna design problems * Chapter 2: Circuit relations, reciprocity theorems * Chapter 3: Radiation from current distributions * Chapter 4: Wavefronts and rays * Chapter 5: Scattering and diffraction * Chapter 6: Aperture illumination and antenna patterns * Chapter 7: Microwave transmission lines * Chapter 8: Microwave dipole antennas and feeds * Chapter 9: Linear-array antennas and feeds * Chapter 10: Waveguide and horn feeds * Chapter 11: Dielectric and metal-plate lenses * Chapter 12: Pencil-beam and simple fanned-beam antennas * Chapter 13: Shaped-beam antennas * Chapter 14: Antenna installation problems * Chapter 15: Antenna measurements - techniques * Chapter 16: Antenna measurements - equipment

Aperture Synthesis with a Non-Regular Distribution of Interferometer Baselines

1974-06-01

J. A. Högbom

A Current Distribution for Broadside Arrays Which Optimizes the Relationship between Beam Width and Side-Lobe Level

1946-06-01

C. L. Dolph

A one-parameter family of current distributions is derived for symmetric broadside arrays of equally spaced point sources energized in phase. For each value of the parameter, the corresponding current distribution … A one-parameter family of current distributions is derived for symmetric broadside arrays of equally spaced point sources energized in phase. For each value of the parameter, the corresponding current distribution gives rise to a pattern in which (1) all the side lobes are at the same level; and (2) the beam width to the first null is a minimum for all patterns arising from symmetric distributions of in-phase currents none of whose side lobes exceeds that level. Design curves relating the value of the parameter to side-lobe level as well as the relative current values expressed as a function of side-lobe level are given for the cases of 8-, 12-, 16-, 20-, and 24-element linear arrays.

Fundamental limitations in antennas

1981-01-01

R.C. Hansen

Four fundamental limitations in antennas have been identified in the areas of: electrically small antennas, superdirective antennas, superresolution antennas, and high-pin antennas. All exhibit roughly exponential increase in cost factors … Four fundamental limitations in antennas have been identified in the areas of: electrically small antennas, superdirective antennas, superresolution antennas, and high-pin antennas. All exhibit roughly exponential increase in cost factors with performance increase beyond the robust range. This paper reviews these limitations. Electrically small antennas are analyzed via spherical mode theory, with the antenna enclosed in a virtual sphere. Minimum Q varies inversely as the cube of sphere radius in radian wavelengths when the radius is much less than the latter. This limits the achievable bandwidth. Superdirective apertures require a constraint; the optimization is generally intractable except for line sources. Superdirective arrays have spacing below half-wavelength, and for small spacings a constraint is desirable to limit Q, tolerances, efficiency, sidelobes, etc. This is accomplished by expressing constrained directivity as a ratio of two Hermilian quadratic forms, for which a solution exists. Array Q varies exponentially with directivity so only modest increases are practical. Superresolution arrays use maximum entropy processes to improve spatial frequency resolution for short samples (short arrays), analogous to spectral analysis processing. An amplitude-tapered autocorrelation function is extended by linear least square prediction and autoregression; the latter contributes filter poles. This extension is with minimum added information, hence maximum entropy. In contrast to superdirective arrays which are all zero functions, superresolution maximum entropy uses an all pole function. Results are dependent upon the sampling subarray size and upon signal/noise (S/N). Required S/N increases exponentially with inverse angular resolution. Achievable gain of high-gain reflector antennas is limited by cost of the structure. For random surface errors maximum gain is proportional to the mechanical tolerance ratio (antenna diameter/1σ tolerance) squared. Since cost increases rapidly with diameter and with tolerance ratio this comprises a gain limitation. Current best reflectors have maximum gain in the range of 90 to 100 dB.

An Introduction to Statistical Communication Theory

2009-01-01

David Middleton

This IEEE Classic Reissue provides at an advanced level, a uniquely fundamental exposition of the applications of Statistical Communication Theory to a vast spectrum of important physical problems. Included are … This IEEE Classic Reissue provides at an advanced level, a uniquely fundamental exposition of the applications of Statistical Communication Theory to a vast spectrum of important physical problems. Included are general analysis of signal detection, estimation, measurement, and related topics involving information transfer. Using the statistical Bayesian viewpoint, renowned author David Middleton employs statistical decision theory specifically tailored for the general tasks of signal processing. Dr. Middleton also provides a special focus on physical modeling of the canonical channel with real-world examples relating to radar, sonar, and general telecommunications. This book offers a detailed treatment and an array of problems and results spanning an exceptionally broad range of technical subjects in the communications field. Complete with special functions, integrals, solutions of integral equations, and an extensive, updated bibliography by chapter, An Introduction to Sta istical Communication Theory is a seminal reference, particularly for anyone working in the field of communications, as well as in other areas of statistical physics. (Originally published in 1960.)

Ultra-low sidelobes from time-modulated arrays

1963-11-01

Wolfgang Kummer , A. Villeneuve , T.T. Fong +1 more

Antenna patterns with ultra-low sidelobes have been obtained for an experimental receiving array designed with time-modulated slot radiators. The technique utilizes on-off RF switches which are programmed in a predetermined … Antenna patterns with ultra-low sidelobes have been obtained for an experimental receiving array designed with time-modulated slot radiators. The technique utilizes on-off RF switches which are programmed in a predetermined sequence to produce the desired pattern. The results of tests on an experimental eight-element slot array designed for sidelobe reduction are presented. Two examples are considered: 1) an initial static pattern with 30-db sidelobes which are reduced to about 40 db by sequential switching and 2) an initial static pattern with 13-db sidelobes which are reduced directly to about 40 db by a different sequence of switching. Measured patterns illustrating the sidelobe reduction are included. The applicability of the sidelobe reduction technique to large electronically steerable phased arrays is considered briefly and it is concluded that it is compatible with such systems.

Physical Limitations of Omni-Directional Antennas

1948-12-01

L. J. Chu

The physical limitations of omni-directional antennas are considered. With the use of the spherical wave functions to describe the field, the directivity gain G and the Q of an unspecified … The physical limitations of omni-directional antennas are considered. With the use of the spherical wave functions to describe the field, the directivity gain G and the Q of an unspecified antenna are calculated under idealized conditions. To obtain the optimum performance, three criteria are used, (1) maximum gain for a given complexity of the antenna structure, (2) minimum Q, (3) maximum ratio of G/Q. It is found that an antenna of which the maximum dimension is 2a has the potentiality of a broad band width provided that the gain is equal to or less than 4a/λ. To obtain a gain higher than this value, the Q of the antenna increases at an astronomical rate. The antenna which has potentially the broadest band width of all omni-directional antennas is one which has a radiation pattern corresponding to that of an infinitesimally small dipole.

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The unifying role of the coarray in aperture synthesis for coherent and incoherent imaging

1990-04-01

R.T. Hoctor , S.A. Kassam

Systems of two-dimensional (2-D) imaging arrays and apertures are considered from the point of view of their performance in the imaging of spatially incoherent as well as coherent source distributions. … Systems of two-dimensional (2-D) imaging arrays and apertures are considered from the point of view of their performance in the imaging of spatially incoherent as well as coherent source distributions. Such systems find applications in radar, sonar, and ultrasound imaging, as well as in applications such as seismology and radio astronomy. For linear imaging techniques related to beamforming and based on the Fourier transform relationship between the source distribution and the aperture plane measurements, the point spread function of the system completely characterizes its performance. This function is determined by the geometry of the physical aperture or array as well as the weighting that can be applied to measurements. It is shown that the introduction of the concept of coarray, both for receive apertures in incoherent imaging and for transmit/receive systems in reflection-mode coherent imaging, provides a convenient and elegant framework within which many apparently isolated techniques for point-spread function or aperture synthesis can be understood. In addition to this unifying role, coarray concept gives new insight into the aperture synthesis process, which allows interesting new imaging techniques to be developed, especially in coherent imaging.

Adaptive Array Principles

1981-01-01

J.E. Hudson

Adaptive arrays are a radical departure from conventional thinking in antenna design, offering substantial improvements in performance over fixed pattern antennas in environments that include severe interference and jamming. They … Adaptive arrays are a radical departure from conventional thinking in antenna design, offering substantial improvements in performance over fixed pattern antennas in environments that include severe interference and jamming. They achieve this because they are designed to steer nulls automatically at noise sources of unknown or variable direction and generally to modify their beampatterns to optimise performance. Adaptive array processing is applicable in most systems that exploit wave propagation; typical uses being radar, active and passive sonar, radio communication links, and radio monitoring. Although sensors and hardware for different applications vary, the same optimality criteria are used throughout and similar algorithms may be employed. This book develops the concepts underlying the design of adaptive arrays from first principles and is directed at research workers and designers whose mathematical background requires refurbishment in the special techniques that have accumulated around the field, often to the obscuration of the simple basic ideas. The topics treated include: single multiple null steering; derivation of the weighting coefficients in an array that maximises signal to noise ratio; online algorithms for achieving these coefficients using gradient methods based on correlators and coefficient peterbation; direct estimation of optimum coefficients by covariance matrix inversion and recursive techniques; prevention of null steering at the desired source and control over the main lobe shape; minimisation of the number of variable coefficients in suboptimal implementations.

Antenna tolerance theory&#8212;A review

1966-01-01

J. Ruze

The theoretical basis of antenna tolerance theory is reviewed. Formulas are presented for the axial loss of gain and the pattern degradation as a function of the reflector surface rms … The theoretical basis of antenna tolerance theory is reviewed. Formulas are presented for the axial loss of gain and the pattern degradation as a function of the reflector surface rms error and the surface spatial correlation. Methods of determining these quantities by astronomical or ground-based electrical measurements are described. Correlation between the theoretical predictions and the performance of actual large antenna structures is presented.

A Note on a Simple Transmission Formula

1946-05-01

H.T. Friis

A simple transmission formula for a radio circuit is derived. The utility of the formula is emphasized and its limitations are discussed. A simple transmission formula for a radio circuit is derived. The utility of the formula is emphasized and its limitations are discussed.

Noise Figures of Radio Receivers

1944-07-01

H.T. Friis

A rigorous definition of the noise figure of radio receivers is given in this paper. The definition is not limited to high-gain receivers, but can be applied to four-terminal networks … A rigorous definition of the noise figure of radio receivers is given in this paper. The definition is not limited to high-gain receivers, but can be applied to four-terminal networks in general. An analysis is made of the relationship between the noise figure of the receiver as a whole and the noise figures of its components. Mismatch relations between the components of the receiver and methods of measurements of noise figures are discussed briefly.

Differential Evolution as Applied to Electromagnetics

2011-02-01

Paolo Rocca , Giacomo Oliveri , Andrea Massa

In electromagnetics, optimization problems generally require high computational resources and involve a large number of unknowns. They are usually characterized by non-convex functionals and continuous spaces suitable for strategies based … In electromagnetics, optimization problems generally require high computational resources and involve a large number of unknowns. They are usually characterized by non-convex functionals and continuous spaces suitable for strategies based on Differential Evolution (DE). In such a framework, this paper is aimed at presenting an overview of Differential Evolution-based approaches used in electromagnetics, pointing out novelties and customizations with respect to other fields of application. Starting from a general description of the evolutionary mechanism of Differential Evolution, Differential Evolution-based techniques for electromagnetic optimization are presented. Some hints on the convergence properties and the sensitivity to control parameters are also given. Finally, a comprehensive coverage of different Differential Evolution formulations in solving optimization problems in the area of computational electromagnetics is presented, focusing on antenna synthesis and inverse scattering.

Advances in Particle Swarm Optimization for Antenna Designs: Real-Number, Binary, Single-Objective and Multiobjective Implementations

2007-03-01

Nanbo Jin , Yahya Rahmat‐Samii

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The particle swarm optimization (PSO) is a recently developed evolutionary algorithm (EA) based on the swarm behavior in the nature. This paper presents recent advances in applying … <para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The particle swarm optimization (PSO) is a recently developed evolutionary algorithm (EA) based on the swarm behavior in the nature. This paper presents recent advances in applying a versatile PSO engine to real-number, binary, single-objective and multiobjective optimizations for antenna designs, with a randomized Newtonian mechanics model developed to describe the swarm behavior. The design of aperiodic (nonuniform and thinned) antenna arrays is presented as an example for the application of the PSO engine. In particular, in order to achieve an improved peak sidelobe level (SLL), element positions in a nonuniform array are optimized by real-number PSO (RPSO). On the other hand, in a thinned array, the <emphasis emphasistype="smcaps">on/off </emphasis> state of each element is determined by binary PSO (BPSO). Optimizations for both nonuniform arrays and thinned arrays are also expanded to multiobjective cases. As a result, nondominated designs on the Pareto front enable one to achieve other design factors than the peak SLL. Optimized antenna arrays are compared with periodic arrays and previously presented aperiodic arrays. Selected designs fabricated and measured to validate the effectiveness of PSO in practical electromagnetic problems. </para>

The active element pattern

1994-01-01

D.M. Pozar

This review article discusses the use of the active element pattern for prediction of the scan performance of large phased array antennas. The introduction and application of the concept of … This review article discusses the use of the active element pattern for prediction of the scan performance of large phased array antennas. The introduction and application of the concept of the active element pattern goes back at least 30 years but the subject is generally not covered in modern antenna engineering textbooks or handbooks, and many contemporary workers are unfamiliar with this simple but powerful idea. In addition, early references on this subject do not provide a rigorous discussion or derivation of the active element pattern, relying instead on a more qualitative interpretation. The purpose of this article is to make the technique of active element patterns more accessible to antenna engineers, and to provide a new derivation of the basic active element pattern relations in terms of scattering parameters.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>

An introduction to genetic algorithms for electromagnetics

1995-04-01

Randy L. Haupt

This article is a tutorial on using genetic algorithms to optimize antenna and scattering patterns. Genetic algorithms are "global" numerical-optimization methods, patterned after the natural processes of genetic recombination and … This article is a tutorial on using genetic algorithms to optimize antenna and scattering patterns. Genetic algorithms are "global" numerical-optimization methods, patterned after the natural processes of genetic recombination and evolution. The algorithms encode each parameter into binary sequences, called a gene, and a set of genes is a chromosome. These chromosomes undergo natural selection, mating, and mutation, to arrive at the final optimal solution. After providing a detailed explanation of how a genetic algorithm works, and a listing of a MATLAB code, the article presents three examples. These examples demonstrate how to optimize antenna patterns and backscattering radar-cross-section patterns. Finally, additional details about algorithm design are given.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>

A Mathematical Theory of Linear Arrays

1943-01-01

S. A. Schelkunoff

A MATHEMATICAL theory, suitable for appraising and controlling directive properties of linear antenna arrays, can be based upon a simple modification of the usual expression for the radiation intensity of … A MATHEMATICAL theory, suitable for appraising and controlling directive properties of linear antenna arrays, can be based upon a simple modification of the usual expression for the radiation intensity of a system of radiating sources. The first step in this modification is closely analogous to the passage from the representation of instantaneous values of harmonically varying quantities by real numbers to a symbolic representation of these quantities by complex numbers. The second step consists in a substitution which identifies the radiation intensity with the norm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> of a polynomial in a complex variable. The complex variable itself represents a typical direction in space. This mathematical device permits tapping the resources of algebra and leads to a pictorial representation of the radiation intensity.

Linear array geometry synthesis with minimum sidelobe level and null control using particle swarm optimization

2005-08-01

Majid Khodier , Christos G. Christodoulou

This paper describes the synthesis method of linear array geometry with minimum sidelobe level and null control using the particle swarm optimization (PSO) algorithm. The PSO algorithm is a newly … This paper describes the synthesis method of linear array geometry with minimum sidelobe level and null control using the particle swarm optimization (PSO) algorithm. The PSO algorithm is a newly discovered, high-performance evolutionary algorithm capable of solving general N-dimensional, linear and nonlinear optimization problems. Compared to other evolutionary methods such as genetic algorithms and simulated annealing, the PSO algorithm is much easier to understand and implement and requires the least of mathematical preprocessing. The array geometry synthesis is first formulated as an optimization problem with the goal of sidelobe level (SLL) suppression and/or null placement in certain directions, and then solved by the PSO algorithm for the optimum element locations. Three design examples are presented that illustrate the use of the PSO algorithm, and the optimization goal in each example is easily achieved. The results of the PSO algorithm are validated by comparing with results obtained using the quadratic programming method (QPM).

Sidelobe reduction in array-pattern synthesis using genetic algorithm

1997-07-01

Keen-Keong Yan , Yilong Lu

A simple and flexible genetic algorithm (GA) for pattern synthesis of antenna array with arbitrary geometric configuration is presented. Unlike conventional GA using binary coding and binary crossover, this approach … A simple and flexible genetic algorithm (GA) for pattern synthesis of antenna array with arbitrary geometric configuration is presented. Unlike conventional GA using binary coding and binary crossover, this approach directly represents the array excitation weighting vectors as complex number chromosomes and uses decimal linear crossover without a crossover site. Compared with conventional GAs, this approach has a few advantages: giving a clearer and simpler representation of the problem, simplifying chromosome construction, and totally avoiding binary encoding and decoding so as to simplify software programming and to reduce CPU time. This method also allows us to impose constraints on phases and magnitudes of complex excitation coefficients for preferable implementation in practice using digital phase shifters and digital attenuators. Successful applications show that the approach can be used as a general tool for pattern synthesis of arbitrary arrays.

Convex Optimization-Based Beamforming

2010-04-23

Alex B. Gershman , Nicholas D. Sidiropoulos , Shahram Shahbazpanahi +2 more

In this article, an overview of advanced convex optimization approaches to -multisensor beamforming is presented, and connections are drawn between different types of optimization-based beamformers that apply to a broad … In this article, an overview of advanced convex optimization approaches to -multisensor beamforming is presented, and connections are drawn between different types of optimization-based beamformers that apply to a broad class of receive, transmit, and network beamformer design problems. It is demonstrated that convex optimization provides an indispensable set of tools for beamforming, enabling rigorous formulation and effective solution of both long-standing and emerging design problems.

Genetic algorithms in engineering electromagnetics

1997-01-01

J.M. Johnson , V. Rahmat-Samii

This paper presents a tutorial and overview of genetic algorithms for electromagnetic optimization. Genetic-algorithm (GA) optimizers are robust, stochastic search methods modeled on the concepts of natural selection and evolution. … This paper presents a tutorial and overview of genetic algorithms for electromagnetic optimization. Genetic-algorithm (GA) optimizers are robust, stochastic search methods modeled on the concepts of natural selection and evolution. The relationship between traditional optimization techniques and the GA is discussed. Step-by-step implementation aspects of the GA are detailed, through an example with the objective of providing useful guidelines for the potential user. Extensive use is made of sidebars and graphical presentation to facilitate understanding. The tutorial is followed by a discussion of several electromagnetic applications in which the GA has proven useful. The applications discussed include the design of lightweight, broadband microwave absorbers, the reduction of array sidelobes in thinned arrays, the design of shaped-beam antenna arrays, the extraction of natural resonance modes of radar targets from backscattered response data, and the design of broadband patch antennas. Genetic-algorithm optimization is shown to be suitable for optimizing a broad class of problems of interest to the electromagnetic community. A comprehensive list of key references, organized by application category, is also provided.

Thinned arrays using genetic algorithms

1994-07-01

Randy L. Haupt

Large arrays are difficult to thin in order to obtain low sidelobes. Traditional statistical methods of aperiodic array synthesis fall far short of optimum configurations. Traditional optimization methods are not … Large arrays are difficult to thin in order to obtain low sidelobes. Traditional statistical methods of aperiodic array synthesis fall far short of optimum configurations. Traditional optimization methods are not well suited for optimizing a large number of parameters or discrete parameters. This paper presents how to optimally thin an array using genetic algorithms. The genetic algorithm determines which elements are turned off in a periodic array to yield the lowest maximum relative sidelobe level. Simulation results for 200 element linear arrays and 200 element planar arrays are shown. The arrays are thinned to obtain sidelobe levels of less than -20 dB. The linear arrays are also optimized over both scan angle and bandwidth.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>

Particle Swarm Optimization Versus Genetic Algorithms for Phased Array Synthesis

2004-03-01

D.W. Boeringer , Douglas H. Werner

Particle swarm optimization is a recently invented high-performance optimizer that is very easy to understand and implement. It is similar in some ways to genetic algorithms or evolutionary algorithms, but … Particle swarm optimization is a recently invented high-performance optimizer that is very easy to understand and implement. It is similar in some ways to genetic algorithms or evolutionary algorithms, but requires less computational bookkeeping and generally only a few lines of code. In this paper, a particle swarm optimizer is implemented and compared to a genetic algorithm for phased array synthesis of a far-field sidelobe notch, using amplitude-only, phase-only, and complex tapering. The results show that some optimization scenarios are better suited to one method versus the other (i.e., particle swarm optimization performs better in some cases while genetic algorithms perform better in others), which implies that the two methods traverse the problem hyperspace differently. The particle swarm optimizer shares the ability of the genetic algorithm to handle arbitrary nonlinear cost functions, but with a much simpler implementation it clearly demonstrates good possibilities for widespread use in electromagnetic optimization.

Minimum-redundancy linear arrays

1968-03-01

A. T. Moffet

It is shown that there is a class of linear arrays which achieves maximum resolution for a given number of elements by minimizing the number of redundant spacings present in … It is shown that there is a class of linear arrays which achieves maximum resolution for a given number of elements by minimizing the number of redundant spacings present in the array. For many-element arrays the degree of redundancy will approach 4/3. Applications of such arrays to aperture synthesis are discussed.

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Antenna array pattern synthesis via convex optimization

1997-03-01

Hervé Lebret , Stephen Boyd

We show that a variety of antenna array pattern synthesis problems can be expressed as convex optimization problems, which can be (numerically) solved with great efficiency by recently developed interior-point … We show that a variety of antenna array pattern synthesis problems can be expressed as convex optimization problems, which can be (numerically) solved with great efficiency by recently developed interior-point methods. The synthesis problems involve arrays with arbitrary geometry and element directivity, constraints on far- and near-field patterns over narrow or broad frequency bandwidth, and some important robustness constraints. We show several numerical simulations for the particular problem of constraining the beampattern level of a simple array for adaptive and broadband arrays.

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Robust minimum variance beamforming

2005-04-19

Robert Lorenz , Stephen Boyd

This paper introduces an extension of minimum variance beamforming that explicitly takes into account variation or uncertainty in the array response. Sources of this uncertainty include imprecise knowledge of the … This paper introduces an extension of minimum variance beamforming that explicitly takes into account variation or uncertainty in the array response. Sources of this uncertainty include imprecise knowledge of the angle of arrival and uncertainty in the array manifold. In our method, uncertainty in the array manifold is explicitly modeled via an ellipsoid that gives the possible values of the array for a particular look direction. We choose weights that minimize the total weighted power output of the array, subject to the constraint that the gain should exceed unity for all array responses in this ellipsoid. The robust weight selection process can be cast as a second-order cone program that can be solved efficiently using Lagrange multiplier techniques. If the ellipsoid reduces to a single point, the method coincides with Capon's method. We describe in detail several methods that can be used to derive an appropriate uncertainty ellipsoid for the array response. We form separate uncertainty ellipsoids for each component in the signal path (e.g., antenna, electronics) and then determine an aggregate uncertainty ellipsoid from these. We give new results for modeling the element-wise products of ellipsoids. We demonstrate the robust beamforming and the ellipsoidal modeling methods with several numerical examples.

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Design of line-source antennas for narrow beamwidth and low side lobes

1955-01-01

T. T. Taylor

It is well known that the phenomenon of radiation from line-source antennas is very similar to that of the diffraction of light from narrow apertures. Unlike the optical situation, however, … It is well known that the phenomenon of radiation from line-source antennas is very similar to that of the diffraction of light from narrow apertures. Unlike the optical situation, however, antenna design technique permits the use of other-than-uniform distributions of field across the antenna aperture. Line source synthesis is the science of choosing this distribution function to give a radiation pattern with prescribed properties such as, for example, narrow angular width of the main lobe and low side lobes. In the present article the mathematical relationships involved in the radiation calculation are studied from the point of view of function theory. Some conclusions are drawn which outline the major aspects of synthesis technique very clearly. In particular, the problem of constructing a line source with an optimum compromise between beamwidth and side-lobe level (analogous to the Dolph - Tchebycheff problem in linear array theory) is considered. The ideal pattern is cos π √ {u /sup 2/ - A/sup 2/} , where u = (2a/λ) cos θ, a is the half-length of the source, and cosh π A is the side-lobe ratio. Because of theoretical limitations, this pattern cannot be obtained from a physically realizable antenna; nevertheless its ideal characteristics can be approached arbitrarily closely. The procedure for doing this is given in detail.

Adaptive arrays

1976-09-01

S. P. Applebaum

A method for adaptively optimizing the signal-to-noise ratio of an array antenna is presented. Optimum element weights are derived for a prescribed environment and a given signal direction. The derivation … A method for adaptively optimizing the signal-to-noise ratio of an array antenna is presented. Optimum element weights are derived for a prescribed environment and a given signal direction. The derivation is extended to the optimization of a generalized signal-to-noise ratio which permits specification of preferred weights for the normal quiescent environment. The relation of the adaptive array to sidelobe cancellation is shown, and a real-time adaptive implementation is discussed. For illustration, the performance of an adaptive linear array is presented for various jammer configurations.

Computational Methods for Electromagnetics

1997-01-01

Andrew F. Peterson , Scott L. Ray , R. Mittra

Phased Array Antenna Handbook

1999-06-01

Array Signal Processing

1989-01-01

S.U. Pillai , C.S. Burrus

The measurement of power spectra from the point of view of communications engineering — Part I

1958-01-01

R. B. Blackman , John W. Tukey

The measurement of power spectra is a problem of steadily increasing importance which appears to some to be primarily a problem in statistical estimation. Others may see it as a … The measurement of power spectra is a problem of steadily increasing importance which appears to some to be primarily a problem in statistical estimation. Others may see it as a problem of instrumentation, recording and analysis which vitally involves the ideas of transmission theory. Actually, ideas and techniques from both fields are needed. When they are combined, they provide a basis for developing the insight necessary (i) to plan both the acquisition of adequate data and sound procedures for its reduction to meaningful estimates and (ii) to interpret these estimates correctly and usefully. This account attempts to provide and relate the necessary ideas and techniques in reasonable detail. Part II of this article wilt appear in the March issue of THE JOURNAL.

Adaptive arrays

1976-09-01

S. Applebaum

A method for adaptively optimizing the signal-to-noise ratio of an array antenna is presented. Optimum element weights are derived for a prescribed environment and a given signal direction. The derivation … A method for adaptively optimizing the signal-to-noise ratio of an array antenna is presented. Optimum element weights are derived for a prescribed environment and a given signal direction. The derivation is extended to the optimization of a "generalized" signal-to-noise ratio which permits specification of preferred weights for the normal quiescent environment. The relation of the adaptive array to sidelobe cancellation is shown, and a real-time adaptive implementation is discussed. For illustration, the performance of an adaptive linear array is presented for various jammer configurations.

Efficient and high-precision adjustment of mesh reflector antenna considering target consistency

2025-06-23

Ruixiang Zhang , Yiqun Zhang , Huai Guan +2 more | Space Science & Technology

Analysis and Design of 1-bit Circularly-Polarized Reconfigurable Transmit-array for Bandwidth and Efficiency Enhancement

2025-06-23

Silong Chen , Kunping Yang , Zhijing Wu +2 more | Optics Express

Using AI to Improve MIMO Antennas with SRR for 26 GHz by Analyzing Data

2025-06-22

Linda Chouikhi , Chaker Essid , M. Bassem Ben Salah +2 more | Electronics

This paper introduces a database-based design methodology aimed at optimizing a 26 GHz MIMO antenna system through machine learning (ML) techniques. The procedure is divided into two primary phases. Initially, … This paper introduces a database-based design methodology aimed at optimizing a 26 GHz MIMO antenna system through machine learning (ML) techniques. The procedure is divided into two primary phases. Initially, a rectangular microstrip patch antenna is designed and enhanced using analytical models alongside ML algorithms that are trained on a detailed dataset of geometric parameters. This yields effective impedance matching (S11 < −45 dB) and a high gain (~6.64 dBi), which serve as the foundation for the MIMO structure. In the second phase, split ring resonator (SRR) configurations are integrated between the antenna elements to reduce mutual coupling. A specialized dataset, featuring varied dimensions of SRR, quantities of unit cells, and spatial placements, is utilized to train Random Forest models that forecast arrangements achieving optimal isolation (S21 < −40 dB) while maintaining low reflection losses. Additionally, a secondary dataset is constructed to investigate the best strategies for SRR placement, ensuring an optimal balance between isolation and return loss. The ultimate MIMO design is validated via comprehensive full-wave electromagnetic simulations and experimental measurements. The proposed system exhibits noteworthy performance enhancements, including an envelope correlation coefficient (ECC) < 0.005, diversity gain (DG) ≈ 9.99 dB, channel capacity loss (CCL) < 0.3 bits/s/Hz, total active reflection coefficient (TARC) < −30 dB, radiation efficiency exceeding 80%, and a maximum gain increase up to 10.22 dB. The close correlation between predicted and measured outcomes validates the effectiveness of the ML-driven approach in expediting antenna optimization for 5G and future applications.

Inverse Design of Microstrip Antennas Based on Deep Learning

2025-06-20

Shiyang Chen , Guang‐Hua Sun , Kai Xu Wang | Electronics

This paper introduces a novel inverse design framework that combines pixelated microstrip antenna modeling, convolutional neural network (CNN), and binary particle swarm optimization (BPSO) to automate the process of generating … This paper introduces a novel inverse design framework that combines pixelated microstrip antenna modeling, convolutional neural network (CNN), and binary particle swarm optimization (BPSO) to automate the process of generating antenna structures from specified performance targets. The framework operates through a streamlined workflow: the radiating patch is discretized into a 10 × 10 binary matrix to enable combinatorial design space exploration; a CNN is trained on 150,000 simulated datasets to predict S-parameters as a surrogate for time-consuming electromagnetic simulations; and BPSO optimizes pixel states guided by a fitness function that minimizes reflection coefficients at target frequencies. By representing the patch as binary pixels, the approach exponentially expands the design space from traditional parametric limits to about 1030 combinatorial possibilities, overcoming the inefficiencies of manual trial-and-error design. Comparative studies with genetic algorithms (GAs) and simulated annealing (SA) demonstrate that the BPSO-CNN framework achieves faster convergence and lower S11 error at target frequencies. This work not only advances the state of the art in intelligent antenna design but also provides a scalable paradigm for automated electromagnetic device optimization.

A comprehensive review of AI and machine learning techniques in antenna design optimization and measurement

2025-06-19

Pradnya A. Gajbhiye , Satya P. Singh , Madan Kumar Sharma | Deleted Journal

Radomizing an Antenna for a SAR-Based ETA Radar System While Ensuring Imaging Accuracy: A Focus on Phase Shifts

2025-06-17

María Elena de Cos Gómez , Alicia Flórez Berdasco , Jaime Laviada +1 more | Micromachines

The impact of radomization on the radiation pattern of a millimeter-wave antenna for an ETA system utilizing synthetic aperture radar (SAR) is examined with special emphasis placed on the phase … The impact of radomization on the radiation pattern of a millimeter-wave antenna for an ETA system utilizing synthetic aperture radar (SAR) is examined with special emphasis placed on the phase shift across both the beamwidth and the bandwidth, rather than the amplitude. Three different radomization approaches, including one based on metasurfaces, are evaluated for a radar antenna operating within the 24.05-24.25 GHz frequency range. Fabricated prototypes, both of the standalone antenna and the radomized version, are tested and compared in terms of electromagnetic image quality. The metasurface-based radome provides the best results among the radomization options analyzed.

A review on soft computing optimization techniques for electromagnetics

2025-06-16

Prashansa , Bharat Singh , Nagendra Kushwaha | Frequenz

Abstract This study delves various nature inspired soft computing optimization and their applications for solving complex electromagnetics optimization problems. As the discipline advances, the integration of soft computing and electromagnetics … Abstract This study delves various nature inspired soft computing optimization and their applications for solving complex electromagnetics optimization problems. As the discipline advances, the integration of soft computing and electromagnetics is expected to drive innovation and broaden the scope of various engineering fields. In the past, there have been efforts to exploit various nature based optimization techniques like Genetic Algorithm (GA), Ant Colony Optimization (ACO), Particle Swarm Optimization (PSO), Differential Evolution (DE), Evolutionary Strategy, Simulated Annealing (SA), Memetic Algorithm (MA), Bacteria Foraging Optimization (BFO), Comprehensive Learning Particle Swarm Optimization (CLPSO), Wind Driven Optimization (WDO) Technique and many more, for solving multi-modal and multi-dimension in area of electromagnetcis, communications, system identifications, power flow optimization, pattern recognition, biomedical, health-care and marketing management etc. Incorporating soft computing techniques – such as Neural Networks (NN), Wind Driven Optimization (WDO), and Genetic Algorithms (GA) etc. – into electromagnetics has demonstrated significant potential in overcoming complex challenges where traditional methods fall short. These methods enhance resilience against the inherent uncertainties and nonlinear characteristics of electromagnetic systems, leading to notable progress in design optimization, antenna pattern synthesis, and mitigating electromagnetic interference.

A Parallel Surrogate-Assisted Multi-Penalty Function Search for Simulation-Driven Antenna Design

2025-06-08

Jin Wang , Qingbin Guo , Haoran Gu +1 more | 2022 IEEE Congress on Evolutionary Computation (CEC)

Small Aperture Antenna Arrays for Direction of Arrival Estimation

2025-06-08

Kurang Mehta , I.J. Gupta | Sensors

In this paper, we establish criteria for the design of small aperture antenna arrays for Direction of Arrival (DOA) estimation. We define a small aperture antenna array as one consisting … In this paper, we establish criteria for the design of small aperture antenna arrays for Direction of Arrival (DOA) estimation. We define a small aperture antenna array as one consisting of a few elements with an average interelement spacing less than or equal to half a wavelength. We use the spatial covariance matrix of the antenna array to derive the design criterion. It is well known that the DOA estimation performance of an antenna array is strongly related to the amount of information in this matrix. Also, the Cramer-Rao Bound of the estimated DOA is closely related to this matrix. We establish and demonstrate that, for optimal DOA estimation performance, a small aperture antenna array should have non-uniformly spaced and dissimilar antenna elements. Since mutual coupling between antenna elements makes their in situ responses dissimilar, instead of mitigating mutual coupling, one should include mutual coupling in the DOA estimation process to enhance the DOA estimation performance of antenna arrays.

Optimization-based compensation method for deformed array antennas considering changed mutual coupling and element deformation

2025-06-01

Qi Wang , Weilin Chen , Junfeng Zheng | AEU - International Journal of Electronics and Communications

Frequency invariant beamformer design exploiting SRV-constrained array response control

2025-06-01

Zihao Teng , Huaguo Zhang , Jiancheng An +2 more | Signal Processing

Design and performance limit of near-field broadband IIR beamformers

2025-06-01

Qi He , Zhiguo Feng , Zhibao Li +1 more | Digital Signal Processing

Robust Optimization Algorithm of RF MEMS Switches Considering Uncertainties

2025-06-01

Hao Yan , Yaolan Jia , Chuangyuan Zeng +2 more | Integration

The Tracking Tapered Gridded Estimator for the 21-cm power spectrum from MWA drift scan observations II: The Missing Frequency Channels

2025-05-31

Khandakar Md Asif Elahi , Somnath Bharadwaj , Suman Chatterjee +4 more | Monthly Notices of the Royal Astronomical Society

Abstract Missing frequency channels pose a problem in estimating the redshifted 21-cm power spectrum P(k⊥, k∥) from radio-interferometric visibility data. This is particularly severe for the Murchison Widefield Array (MWA), … Abstract Missing frequency channels pose a problem in estimating the redshifted 21-cm power spectrum P(k⊥, k∥) from radio-interferometric visibility data. This is particularly severe for the Murchison Widefield Array (MWA), which has a periodic pattern of missing channels that introduces spikes along k∥. The Tracking Tapered Gridded Estimator (TTGE) overcomes this by first correlating the visibilities in the frequency domain to estimate the multi-frequency angular power spectrum (MAPS) Cℓ(Δν) that has no missing frequency separation Δν. We perform a Fourier transform along Δν to estimate P(k⊥, k∥). Simulations demonstrate that the TTGE can estimate P(k⊥, k∥) without any artifacts due to missing channels. However, the spikes persist for the actual foreground-dominated data. A detailed investigation, considering both simulations and actual data, reveals that the spikes originate from a combination of the missing channels and the strong spectral dependence of the foregrounds. We propose and demonstrate a technique to mitigate the spikes. Applying this, we find the values of P(k⊥, k∥) in the region 0.004 ≤ k⊥ ≤ 0.048 Mpc−1 and k∥ &gt; 0.35 Mpc−1 to be consistent with zero within the expected statistical fluctuations. We obtain the 2σ upper limit of $\Delta _{\rm UL}^2(k)=(934.60)^2\, {\rm mK^2}$ at k = 0.418 Mpc−1 for the mean squared brightness temperature fluctuations of the $z$ = 8.2 epoch of reionization (EoR) 21-cm signal. This upper limit is from ∼17 minutes of observation for a single pointing direction. We expect tighter constraints when we combine all 162 different pointing directions of the drift scan observation.

Principles of WEC Arrays

2025-05-30

Zhi Yung Tay | CRC Press eBooks

Main lobe shifting and splitting of 2D symmetric Airy beams via digital phase modulation

2025-05-29

Hao Ni , Yufei Li , Jianfeng Wang +2 more | Applied Optics

A DESIGN OF L-BAND CHORD CIRCULAR HORN LIKE BOW TIE ANTENNA FOR SATELLITE NAVIGATION APPLICATION

2025-05-28

S Bhoopalan , M - Madheswaran , U. Saravanakumar +1 more | International Journal For Multidisciplinary Research

This paper presents the design of a Chord circular horn like bow tie antenna intended for millimeter wave applications within the frequency range of 2.4 GHz to 7 GHz. A … This paper presents the design of a Chord circular horn like bow tie antenna intended for millimeter wave applications within the frequency range of 2.4 GHz to 7 GHz. A multi- objective function is formulated to optimize both the bandwidth and gain of the proposed antenna. The design of the antenna employs FR4 dielectric material, characterized by a dielectric constant (εr) of 4.4 and a loss tangent (δ) of 0.001. Following the successful optimization of the proposed antenna, its performance is assessed by evaluating the return loss and gain characteristics. Finally, after fulfilling the predefined objectives, an analysis of the radiation characteristics is conducted to gain insights into the antenna's radiation properties in E-plane and H-plan. This antenna is suitable for satellite navigation purpose.

High resolution beam-forming for wide-band LFM chirps using super nested arrays

2025-05-28

G. Sreekumar , Sanjana Shaju Kunampilavu , V. Lakshmi +3 more | Sadhana

Convex Formulations for Antenna Array Pattern Optimization Through Linear, Quadratic, and Second-Order Cone Programming

2025-05-28

Álvaro F. Vaquero , Juan Córcoles | Mathematics

This work presents a comprehensive study on formulations for the radiation pattern design of antenna arrays through convex optimization techniques, with a focus on linear, quadratic, and second-order cone programming. … This work presents a comprehensive study on formulations for the radiation pattern design of antenna arrays through convex optimization techniques, with a focus on linear, quadratic, and second-order cone programming. The proposed approaches heavily rely on the construction of Hermitian forms to systematically build convex optimization problems for synthesizing desired beam patterns while including practical constraints such as sidelobe levels (SLLs), maximum directivity, and null placement. By formulating the radiation pattern synthesis problem through a convex formulation, global optimality and computational efficiency are ensured. The paper introduces the mathematical foundations of the proposed methodologies, detailing the structure and benefits of each convex optimization model. Numerical examples demonstrate the effectiveness of the proposed methodologies in achieving high-performance radiation patterns for circular and planar arrays. The results highlight trade-offs between formulation complexity and pattern performance across different optimization models, providing valuable insights for antenna array pattern synthesis. Overall, this work underscores the potential of convex optimization in antenna array pattern synthesis methodologies.

Cluster-based beamforming for enhanced array processing

2025-05-27

Roshdy K. Korayem , Samir Bendoukha

Low-Frequency Square Kilometer Array Pattern Optimization via Convex Programming

2025-05-24

Giada M. Battaglia , Giuseppe Caruso , Pietro Bolli +3 more

A well-known and powerful convex optimization strategy is exploited to enhance the electromagnetic performance of the Square Kilometer Array Low-Frequency radio telescope. The proposed method minimizes the peak sidelobe level … A well-known and powerful convex optimization strategy is exploited to enhance the electromagnetic performance of the Square Kilometer Array Low-Frequency radio telescope. The proposed method minimizes the peak sidelobe level while ensuring full control of the receiving pattern across the entire angular domain. The approach is validated through full-wave simulations that incorporate realistic embedded element patterns, demonstrating significant improvements in sidelobe suppression despite the geometric constraints of the array structure. The achieved results underscore the method’s potential for high-performance beam synthesis in large-scale radio astronomy arrays.

MAOA: A Swift and Effective Optimization Algorithm for Linear Antenna Array Design

2025-05-23

Anoop Raghuvanshi , Abhinav Sharma , Abhishek Awasthi +5 more

This paper presents the modified arithmetic optimization algorithm (MAOA), a swift and effective optimization algorithm specifically designed for electromagnetic applications. Its primary advantage is its ability to avoid local minima … This paper presents the modified arithmetic optimization algorithm (MAOA), a swift and effective optimization algorithm specifically designed for electromagnetic applications. Its primary advantage is its ability to avoid local minima by striking a balance between global exploration and local exploitation searches. This equilibrium is maintained through three key improvements: an enhanced initialization process, a distinctive guidance mechanism for steering searches, and an additional learning phase to refine newly found solutions. This process innovation significantly boosts MAOA’s performance in addressing both constrained and unconstrained optimization challenges. In this study, MAOA is applied to optimize the spacing and current amplitude of linear antenna array (LAA) elements, with the goal of minimizing peak side lobe level (PSLL), close-in side lobe level (CSLL), and overall side lobe level (SLL), both with and without constraints on first null beamwidth (FNBW), as well as null positioning with SLL minimization. Ten designs, comprising 10 and 20 antenna elements of LAA and one 14-element circular antenna array (CAA), showcase MAOA’s proficiency in antenna array pattern synthesis. Optimizing element positions results in a PSLL of −21.28 dB, a CSLL of −34.50 dB, and a null depth of −89.00 dB, while optimizing current amplitude achieves a PSLL of −24.32 dB, a CSLL of −29.73 dB, and a null depth of −77.60 dB across various antenna designs. Simulation results reveal that MAOA significantly surpasses traditional uniform linear arrays (ULA) and established optimization techniques. Its superiority is further confirmed through a Wilcoxon rank-sum and Friedman test.

Leveraging Artificial Intelligence for Enhanced Performance Prediction in Micro Strip Antenna Arrays

2025-05-23

Swapna Mudey | Journal of Information Systems Engineering & Management

Micro strip antenna arrays play a pivotal role in modern communication systems due to their compact size, lightweight design, and versatile applications. Despite these advantages, accurately predicting their performance poses … Micro strip antenna arrays play a pivotal role in modern communication systems due to their compact size, lightweight design, and versatile applications. Despite these advantages, accurately predicting their performance poses significant challenges due to the complex interdependencies of design parameters and environmental factors. This research explores the integration of Artificial Intelligence techniques, emphasizing the potential of artificial intelligence (AI) and neural networks, to enhance the accuracy of performance prediction for microstrip antenna arrays. The proposed methodology employs a deep neural network (DNN) model that learns intricate patterns and nonlinear relationships among design variables, including substrate materials, geometries, and operational frequencies. By leveraging supervised learning on an extensive dataset of antenna configurations, the model demonstrates exceptional predictive accuracy for critical performance metrics such as gain, bandwidth, radiation efficiency, and beam steering capabilities. Simulation results underscore the effectiveness of the DNN approach, achieving prediction accuracies that outperform traditional analytical and empirical methods. Additionally, comparative evaluations with other Artificial Intelligence techniques, such as support vector machines and decision trees, highlight the superiority of neural networks in handling high-dimensional parameter spaces and complex nonlinearities. The results further reveal the computational efficiency of the proposed model, making it suitable for real-time performance optimization in practical applications. This study also presents a detailed analysis of simulation outcomes, showcasing the alignment between predicted and measured results. The visualizations of antenna patterns and performance metrics provide deeper insights into the predictive capabilities of the model. By integrating AI-driven solutions, this research contributes to advancing antenna design workflows, enabling engineers to develop high-performance and cost-effective antenna systems with reduced prototyping cycles. The findings affirm the transformative potential of machine learning, particularly neural networks, in addressing longstanding challenges in microstrip antenna design, paving the way for innovation in communication technology.

Efficient WL Beamforming with Projection onto Interference Null Space

2025-05-22

Yang-Ho Choi

Synthetic-Aperture Passive Localization Utilizing Distributed Phased Moving-Antenna Arrays

2025-05-22

Xu Zhang , Guohao Sun , Dingkang Li +2 more

This article presents a Synthetic-Aperture Distributed Phased Array (SADPA) framework to address emitter localization challenges in dynamic environments. Building on Distributed Synthetic-Aperture Radar (DSAR) principles, SADPA integrates distributed phased arrays … This article presents a Synthetic-Aperture Distributed Phased Array (SADPA) framework to address emitter localization challenges in dynamic environments. Building on Distributed Synthetic-Aperture Radar (DSAR) principles, SADPA integrates distributed phased arrays with motion-induced phase compensation, enabling coherent aperture synthesis beyond physical array limits. By analytically modeling and compensating nonlinear phase variations caused by platform motion, we resolve critical barriers to signal integration while extending synthetic apertures. An improved MUSIC algorithm jointly estimates emitter positions and phase distortions, overcoming parameter coupling inherent in moving systems. To quantify fundamental performance limits, the Cramer–Rao bound (CRB) is derived as a theoretical benchmark. Numerical simulations demonstrate the SADPA framework’s superior performance in multi-source resolution and positioning accuracy; it achieves 0.012 m resolution at 10 GHz for emitters spaced 0.01 m apart. The system maintains consistent coherent gain exceeding 30 dB across both the 1.5 GHz communication and 10 GHz radar bands. Monte Carlo simulations further reveal that the MUSIC-DPD algorithm within the SADPA framework attains minimum positioning error (RMSE), with experimental results closely approaching the theoretical CRB.