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In this paper, the problem of array pattern synthesis is considered by developing two array response control algorithms. The devised two algorithms build on the basis of the accurate array response control (A2RC) approach, and both of them have closed-form solutions and low computational complexities. More specifically, the first proposed algorithm realizes multi-point array response control from an any given weight vector, and the second algorithm modifies the first one by avoiding the possible beam axis shift. The proposed two algorithms are able to control array responses accurately under the conditions of independence on steering vectors. By applying the first and the second array response control algorithm, two effective pattern synthesis methods for focused patterns and shaped patterns are devised, respectively. Representative examples are presented to demonstrate the performance of the proposed algorithms in array response control and pattern synthesis.

In practical scenarios, there are always array errors, which would increase the sidelobe level (SLL) of the array and distort the performance of the electronic devices consequently. Nevertheless, most of the reported works do not take these unavoidable errors into consideration when implementing array beampattern synthesis. To remedy this problem, a low sidelobe beampattern synthesis approach is proposed in the presence of array errors based on the bat algorithm (BA). In particular, the covariance matrix of the sidelobe region in the presence of array errors is incorporated into the optimization problem. Generally, there are many factors that would contribute to array errors in practical scenarios. Therefore, to reduce the influence of the uncertainty characteristic of the errors on the low-SLL beampattern synthesis, the statistical mean method is utilized to obtain a robust calculation of the covariance matrix in the presence of array errors. Theoretical analysis using signal processing technique and electromagnetic simulation using Ansoft HFSS workbench are combined to testify the effectiveness of the proposed approach. Numerical results show that peak SLLs (PSLLs) of around −22dB and −20dB can be respectively achieved in the above two simulation situations with the obtained weight vectors.

The Rotary-Motion Extended Array Synthesis spacecraft is a dual-spin spacecraft with long tethers held in tension by the spin. This paper derives the free-space (not considering orbital effects) dy...

Phase-only nulling with low sidelobe level is a problem of interest in array synthesis which is a tedious problem without an analytical solution. In this communication, a novel framework for the phase-only nulling based on radial basis function neural network (RBFNN) is proposed to predict the phase adjustment for the array pattern nulling with sidelobe control. In the process of network training, the parameters of the RBFNN are optimized simultaneously based on the self-adaptive differential evolution (SADE) algorithm, which aims to improve the approximation ability and reduce the complexity of the network. Simulation results of the optimized RBFNN models show compact network structure and form the array pattern under desired performance with good generalization capability.

In this paper, we propose a new amplitude-only method for pattern synthesis of uniform linear array (ULA) based on genetic algorithm (GA) and artificial neural network (ANN), which can produce a low sidelobe pattern with deep nulls. Unlike existing schemes for pattern synthesis, our method can avoid falling into local optimum and exhibits a faster convergence speed, and is also easy to implement due to its low computational complexity. In complicated and changing environments, the proposed method can quickly and accurately synthesize the desired pattern of the ULA. Numerical results demonstrate the effectiveness of the devised algorithm.

Given an antenna array and a digital beamformer, one can form individually steerable multi‐beams using adaptive beamforming algorithms, but this is achieved at the high cost of both analog and digital hardware, as well as energy consumption. This chapter addresses a number of array synthesis problems facing the design of 5G, 6G, and beyond arrays. These include the synthesis of thinned arrays to save cost; the synthesis of antenna arrays using element rotations to simplify the feed network; the synthesis of sum and difference patterns for communications with moving platforms; and the synthesis of single input multiple output multi‐beam arrays. Detailed synthesis algorithms are presented to illustrate the advantages of an array with rotated elements to meet such wireless communication system requirements. Two examples of synthesizing sum and difference patterns using rotated dipole array elements are examined to demonstrate the efficacy of the approach.

This letter presents a rotation-based optimization method for pattern synthesis of subarrayed phased arrays. In order to keep a good beam scanning ability at different steering angles, the optimization problem is reasonably defined where the objective is taken as minimizing the maximum sidelobe level at a series of steering angles, and both the arrangement variables and the scanning variables are optimized simultaneously. The mutual coupling of the iteratively rotated arrays is rigorously considered in the synthesis. In order to solve the synthesis problem effectively, the design sensitivities are derived analytically and the synthesis is actualized by using a gradient-based algorithm. Typical examples, with considering different regular subarray configurations and the state-of-art irregular subarray configurations, are provided to validate the effectiveness of the proposed approach.

In many practical applications, the antenna arrays are not accurately implemented as desired, resulting in the degradation of sidelobe level. This letter proposes a robust pencil beam pattern synthesis (PBPS) algorithm that is adaptive to the uncertainties of array position. The proposed algorithm, first, sets up the position-variation-related PBPS optimization problem, and then rewrites the position-related parameter, i.e., the array factor, into a high-order Taylor expansion with respect to the array position variation. Thereafter, an iterative processes are designed to estimate the position variation. Finally, the optimal array excitation is calculated by solving the related PBPS problem, in which the estimated array position is used. Simulations with both isotropic element pattern and active element pattern are carried out and the results are compared with the results achieved from the existing work to validate the superiority of the proposed algorithm.

In this paper, the authors propose to design thinned sparse planar array antenna in multiple planes using meta-heuristic optimization algorithm such as Teaching Learning-Based Optimization (TLBO) a...

A new Fourier Transform (NFT) approach is developed for the synthesis of shaped patterns radiated by linear antenna arrays. The proposed method exploits in an innovative way the FT relation between the source distribution and the radiated pattern. Precisely, the finite dimension of real sources is firstly taken into account by using the sampling theorem to approximate the desired pattern as a band-limited function. It is this step that allows one to obtain an important performance improvement. Then, a continuous source is evaluated from the approximate desired pattern to finally obtain the element excitations. Numerical examples validate the method.

This letter proposes a method based on primary-dual iteration to address the array pattern synthesis problem of minimizing the peak sidelobe level (PSL) under the constraints of controlled mainlobe ripples and dynamic range ratio (DRR) of current excitations. Especially, when DRR = 1, the phase-only beampattern synthesis problem is solved. Simulation examples are presented to verify the effectiveness of the proposed method in terms of PSL and DRR.

In this letter, a new algorithm is presented for synthesizing large linear and planar arrays. To reduce the system cost and implementation complexity, the large array is partitioned into multiple disjoint subarrays and is only weighted at subarray level. By the approximation of the optimization objective, the pattern synthesis problem is first formulated as a weight matching problem. Subsequently, a clustering methodology named $K$ -means approach is adopted to solve this problem. The proposed algorithm can produce a good-shaped pattern, which has lower peak sidelobe level than that synthesized by the state-of-the-art method. Numerical results demonstrate the effectiveness of the proposed algorithm.

The generation process of difference beam is analyzed from the perspective of beam superposition. By analyzing the continuous linear source, a differential beam synthesis method, which can control the sidelobes level, is proposed with a simple form. The sidelobes level of the difference pattern is determined by controlling the direction of the subbeam and applying the traditional synthesis method, such as Chebyshev method and Taylor method. The proposed synthesis method is theoretical and explicit. Examples are presented for assessing the capabilities of the synthesis of difference patterns. The general distribution function is given.

A shaped beam pattern (SBP) synthesis algorithm, which obtains the desired SBP in an analytical way, is proposed. The new algorithm describes the SBP with the weighted superposition of a set of pencil beam patterns (PBPs). First, the array weight of the PBP is obtained via analytical algorithms, such as; Chebychev and Taylor, etc. Then, by computing the weights of the PBPs with the least‐square method, the synthesized SBP is expressed explicitly. Different from the state‐of‐the‐art algorithms, the proposed algorithm can obtain the desired SBP analytically, avoiding the time‐consuming iteration processes. Moreover, the proposed algorithm enables the array antenna to scan the beam in different directions. Simulations with linear and planar array antennas are provided to assess the superiority and effectiveness of the proposed algorithm.

An efficient multibeam pattern synthesis method for time modulated array (TMA) is proposed in this paper. The aim of this method is to generate a beam pattern on the specified sideband of TMA. The pattern synthesis problem is divided into two stages. In the first stage, the sequential convex optimization method is used to suppress the sidelobe of the center frequency and reduce the amplitude dynamic range ratios (DRR). In the second stage, the iterative convex optimization method is used to realize the multibeam pattern synthesis in the sideband. Owing to the introduction of convex optimization, the proposed method could be more efficient than approaches using a global optimization algorithm. The proposed method is capable of realizing pattern synthesis under different DRR constraints and different beam radiation directions. Numerical examples of two beams and four beams patterns of 1000-element time modulated linear array verify the effectiveness of the proposed method.

The paper describes monopulse radar with sidelobe-blanking system. The antenna of the sidelobe-blanking system is one subarray of the radar’s active phased array antenna. The elements of the subarray is also used for sum and difference pattern generation. It is shown that if aperture distribution required to produce low-sidelobe sum pattern is used, the pattern of one subarray will satisfy the requrements for antenna of the sidelobe-blanking system. An example of designing the monopulse radar with sidelobe-blanking system is presented. Sum pattern of the radar anettena is produced with different low-sidelobe pattern synthesis procedures. The analysis of monopulse radar parameters and sidelobe-blanking system performance is done.

We present a cylindrical dual-polarization phased array antenna for weather surveillance radars that features high isolation, matched copolar beams, low sidelobe levels, and adaptive null steering. We present a crossed dipole antenna element to replace the patch antenna on the currently deployed cylindrical polarimetric phased array radar (CPPAR). The crossed dipole element offers suppressed surface wave and lower coupling between adjacent elements of an array. As a result, we achieved lower backlobe and sidelobe levels, and a higher match between copolar beams of CPPAR compared to the currently deployed multi-layer patch antenna. Further reduction of the sidelobe level and adaptive null steering are obtained using a modified particle swarm optimization. The proposed null steering mitigates the interference among the four concurrent beams of a cylindrical phased array radar. The improvement in CPPAR radiation characteristics has been verified by comparing the presented crossed dipole antenna’s radiation patterns and the existing aperture coupled patch antenna. The proposed crossed dipole phased array can benefit national weather radar networks to provide accurate multiparameter measurements enabling reliable observation of severe weather phenomena.

Various methods have been proposed to control the electromagnetic fields in the near-or far-field region, one of which is to use antenna arrays. This paper reviews a technique, called the method of maximum power transmission efficiency (MMPTE), for the design of antenna arrays and wireless power transmission (WPT) systems. The method is motivated by the fact that all wireless systems aim to maximize the power transmission efficiency (PTE) between the transmitter and receiver and the PTE can thus be considered as a performance index for the design of WPT system and antenna as well. The MMPTE makes use of the PTE as the performance index to be optimized, and reduces a field synthesis problem into a circuit analysis problem, and is therefore easy to master and implement. It overcomes all the challenges associated with conventional array design methods, and is applicable to the design of any type of antenna array in any environment. This paper summarizes the basic theory of MMPTE and demonstrates MMPTE through a number of near- and far-field applications, including focused antennas, smart antennas, shaped beam antennas, end-fire antennas, multi-beam antennas, polarization-reconfigurable antennas, and wireless power transmission systems.

A low-profile transmissive metasurface is proposed to synthesize contour beam pattern for a European region. A slot array feed is used to illuminate same size metasurface aperture with a plane wave at a near field distance of 24 mm. A two step optimization process is proposed to solve asymmetric and complicated pattern synthesis problem for transformation of plane wave to contour beam pattern using modified Alternating Projection Method (APM). A new subwavelength 4-arm spiral element is proposed to achieve desired performance for contour beam pattern synthesis in $Ku$ band centered at 12.5 GHz. A prototype of low profile transmissive metasurface is also fabricated and measured to verify its gain and bandwidth performance for contour beam pattern synthesis for the European region.

The techniques on the generation of multiple solutions in shaped-beam pattern synthesis are standardly focused on the use of patterns with complex nature as input. Otherwise, in order to derive a symmetric pure real distribution from the canonical pattern synthesis techniques, a generation of a pure-real pattern has to be imposed. In the present work, the exploitation of the multiplicity of the shaped pattern generated by this symmetric pure real distribution is proposed, without constraining the solutions to necessarily meet the pure-real pattern requirement. Therefore, an increase on the degrees of freedom is produced and a greater number of continuous distributions (presenting different natures) is achieved, by omitting the restrictions found in the state-of-the-art methodologies. Thus, a general multiplicity of solutions can be reached and the design protocol can increase its number of alternatives for facing different feeding network structures. In such a way, this article is devoted to illustrate the improvements in terms of number of feasible solutions reached by the general method, including alternative symmetric pure real distributions as input within the procedure. In this manner, two different approaches, constraining the pattern to present the same number of ripples or a similar main beam width, are discussed. Examples of both Taylor distributions linear and circular are illustrated.

An optimization method of pattern synthesis is proposed for peak sidelobe level (PSLL) suppression and null controlling via element rotation and phase optimization. The purpose of this method is to...

Antenna arrays with low sidelobe patterns and high directivities are very desirable in practice and represent a key success for many communication systems such as radio telescopes, satellites, fift...

One of the ultimate targets of array pattern synthesis is to maintain the mainbeam while suppressing the peak sidelode level (PSLL) within a smaller aperture size. The mainbeam gain proportionally increases with the aperture size, whereas the PSLL is uncorrelated approximately. This regular is useful for adjusting the array pattern as changing the aperture size. However, when the mutual coupling effect among the coupled array elements is considered, for some kinds of nonuniform arrays, e.g., the concentric ring array or the concentric elliptical array (CEA), the PSLL property would change significantly when the same array arrangement with different aperture sizes is used. On the purpose of both the PSLL suppression and the aperture reduction, this letter presents a pattern synthesis approach of real coupled CEAs. The form of elliptic ring is mainly introduced for the aperture reduction, and the ellipse-axis ratio, together with the ring radii and the position of each array element along the elliptic rings, are optimized simultaneously for the PSLL suppression. Typical examples are provided to validate the effectiveness of the synthesis approach. This approach also gives an alternative way for the adjustment of real coupled arrays after the theoretical synthesis.

This letter proposes a new power gain pattern synthesis-based (PGPS-based) algorithm for maximizing the minimum array power gain in a wide-beam mainlobe via linear programming. The existing PGPS-based algorithm has been proved to outperform the existing shaped beam pattern synthesis based (SBPS-based) algorithms. However, its optimal solution to the PGPS problem can only be obtained via iterative procedures and its convergence cannot be theoretically guaranteed. One disadvantage of this nonconvergence is that the desired sidelobe level (SLL) might be unobtainable. This letter reformulates the original PGPS problem and transforms it into an approximately equal convex form. As a result, the convergence of the proposed algorithm is ensured and the desired SLL can always be obtained. Moreover, the proposed algorithm can accelerate the computational time. Its performance is assessed with HFSS simulated data by comparing it with the existing PGPS-based algorithm and the SBPS-based algorithms.

This study proposes an array synthesis horn antenna with an extended horn and a stepped corrugated structure for a high-power microwave system. The horn antenna is designed by joining four pyramidal horn antennas and an extended horn to obtain a high gain. To improve the beam pattern in the H-plane, the length of the vertical junction of the pyramidal horns is controlled. Two-stepped and partitioned corrugated structures are attached to both horizontal edges of the aperture for a good front-to-back ratio. The designed 2 × 2 array synthesis horn antenna has a gain of 19.7 dBi and front-to-back ratio of 39.6 dB in the measurement.

In this article, we investigate a novel iterative antenna array synthesis method. The method is based on the iterative addition of antenna array elements. After defining the synthesis algorithm, we prove that the discrepancy between the goal and the synthesized pattern converges to the theoretical lower bound in the sense of a certain norm. The algorithm is also extended to iteratively replace already placed elements and for the synthesis of multiple goal patterns with the same array geometry but with different excitations. Some numerical examples are shown to illustrate the convergence properties of the proposed method. Possible applications include circularly polarized patterns, since the algorithm can handle the rotation as well as translation of the antenna elements.

Mobile communications and spatial detection require antennas with high directive radiation pattern. The main aim of this paper is to achieve directive by reducing side lobes for linear antenna array. As the derivative based optimization is prone to level maxima, invasive weed optimization has been with tuning of vital parameters (d, noEl, noff). Being derivative free IWO with parameters tuning has achieved maximum reduction of side lobes from −13.2 db to −19.8 db. The result is encouraging slowly supervision over standard IWO. Another further is possible by Chao theory.

In this paper, a chamfer distribution antenna array is designed to generate a deflecting circular-polarized vortex beam carrying orbital angular momentum (OAM) mode. When the vortex beam is designed with a deflection angle, the sidelobe of the vortex beam will deteriorate. In order to solve this problem, an optimized array design is presented in this paper. Inspired by the Chebyshev distribution array synthesis method, the antenna elements in the four corners of the antenna array are cut out to realize the chamfer distribution array. Therefore, the sidelobe level of the deflected vortex beam can be effectively suppressed. Moreover, a simplified feeding network is designed to reduce the feeding network complexity by using circularly polarized structural center antenna element. The designed antenna array is simulated, fabricated, and measured at center frequency of 4.25 GHz in C-band. The far-field radiation pattern of the deflected vortex beam and the near E-field OAM vortex beam distribution are simulated and measured to verify the effectiveness of the proposed design method for sidelobe suppression array.

A two-dimensional (2-D) discrete dielectric lens antenna is designed to radiate fan-shaped multi-beam patterns for gain stability in beam switching. The target is to minimize adjacent-beam overlapping transition regions and provide sufficient and similar gains for all field angles when the antenna is employed in a mobile device. This design starts with a conventional 2-D Luneburg lens antenna, and distorts its dielectric permittivity and the sizes of discrete dielectric rings to defocus the pencil beam patterns into shaped ones with a relatively flat pattern for uniform field distribution. The design is realistically implemented at 38 GHz with both simulation and measurement results shown to validate the concept. Successful validation of feasibility in beam synthesis is achieved. Fabrication discrepancy to result in slight radiation degradation is also discussed.

The potentialities offered by antenna arrays make them very attractive for future communication systems. Recent channel measurement at millimeter-waves (mmWaves) have in fact shown that the angular dispersion of the interference follows specific distributions, which are often Gaussian. Accordingly, this paper proposes a phase-only synthesis algorithm for antenna arrays, able to generate patterns having Gaussian shaped nulls to properly suppress the interference. The developed method is suitable for arrays of arbitrary geometry and can operate in the three-dimensional (3D) scenario, thus performing zenith-azimuth synthesis. To prove the effectiveness of the proposed solutions, numerical results involving multi-ring arrays are presented.

An iterative reweighted approach based on convex optimization for the array pattern synthesis is presented. The algorithm consists in solving the problem of auto-specifying the mainlobe width. In the optimization procedure, a slack variable is introduced in the region near the mainlobe region of a pattern. The value of the slack variable will change as well as the width of the region will be narrower based on iterations. The result is that the width of the region is equal to the width of mainlobe region. Representative simulation is provided to demonstrate the effectiveness of the proposed method in beampattern synthesis.

Time-modulated rotationally symmetric circular array (TMRSCA) is designed and synthesized in this paper. All the elements are distributed over the Q annular sectors and controlled by Q high speed RF switches, respectively. The element number in each annular sector, the specific time sequences, and the element positions are optimized by the improved harmony search (ImHS) algorithm for the sidelobe level (SLL) suppression at the operating frequency. An example is presented and the numerical results are compared with several previously published solutions, which illustrated the potential advantages of TMRSCA in time-modulated circular planar array design.

This paper proposes a new array synthesis method for large linear arrays. Traditional large arrays usually have some challenges, such as high cost and complex feeding networks. Partitioning the large array into disjoint subarrays can effectively reduce these problems. In this paper, the K-means method and the convex optimization method are combined to effectively solve the above problems. Compared to other methods, the proposed method can obtain lower sidelobe level.

The problem of optimised design of diversely polarised sparse array for joint synthesis of spatial and polarisation beampattern is addressed in this Letter. Two kinds of polarised array configurations, cocentred and non-cocentred crossed-dipole arrays, are considered. Minimum interelement spacing constraint along with non-cocentred constraint are involved in the design methods by using two discrete linear operators. The optimisation process can be formulated as a mixed-integer quadratically constrained programming problem which guarantees the optimal solution of the sparse array configuration. Comparison examples with state-of-the-art method validate the advantages of the proposed method in terms of the reduction of required element number and the enlargement of adjacent element spacing.

In this paper, the pattern synthesis of conformal antenna array using Salp Swarm Whale Optimization Algorithm (SSWOA) algorithm is proposed. The proposed hybrid algorithm is the combination of Salp Swarm Optimization (SSA) and Whale Optimization Algorithm (WOA). In the proposed algorithm, the SSA algorithm plays the role of guiding the evolution and the WOA algorithm works as an assistant. Moreover, after updating the salps position, with WOA the best known position are evolved to enhance the optimum search ability. When applied to antenna array pattern synthesis by taking advantages of SSA and WOA, the proposed optimization has high convergence accuracy and faster convergence speed. Several typical test functions and optimization examples of a linear array pattern synthesis are illustrated to show the performance of the hybrid algorithm. Experimental results show that the proposed hybrid algorithm is superior to SSA and WOA when applied to Sphere, Griewank, Rosenbrock, and Rastrigin test functions. Keywords: Pattern synthesis, Conformal antenna, Convergence speed, Linear array, Sphere, Griewank, Rosenbrock, Rastrigin

A four-element moxon antenna array is proposed in this paper. Its directive properties are shown with simulations and compared with the classical dipole array. In order to synthesize the pattern of moxon array, a hybrid method that consists of differential evolution (DE) and numerical electromagnetics code version 2 (NEC2) is also introduced. Basically, the cost function used by DE is designed with the help of NEC2 simulations to achieve more realistic optimum antenna array designs. Patterns having one and double sidelobe suppression at predetermined angles are successfully synthesized by using this method whereas the gain value is maintained properly. Robustness of the proposed method is also examined. For this aim, multiple executions of the method implementation are performed under same conditions. The results show that the method introduced in this paper is very stable in terms of the radiation pattern and convergence curves.

In this paper, a new array synthesis approach is developed for the design of reconfigurable sparse arrays radiating sum and difference patterns. The proposed approach provides a significant...

The synthesis of frequency-scanned monopulse radiation patterns using an array of two leaky-wave antennas (LWAs) is demonstrated. The LWA array must be designed with appropriate shifted frequency-dispersion responses to fulfill the desired monopulse-scanning specification over the required bandwidth and number of channels. This is demonstrated using two manufactured LWAs in half-width microstrip technology, designed to scan in the band from 2.39 to 2.65 GHz covering a field of view (FoV) from −80° to +80° and using three frequency channels. Also, this paper addresses the procedure to estimate the direction of arrival (DoA) of an incoming beacon RF signal composed by prescribed tones distributed in the scanning band. This type of multicarrier beacon signals can be produced in wireless systems which allow for frequency-hopping operation. It is demonstrated that the proposed monopulse DoA-estimation technique combines good angular resolution and wide FoV using a simple passive antenna structure.

A hybrid approach to the synthesis of sparse arrays radiating shaped or focused beampattern is presented in this paper. Specifically, an iterative scheme is used where the prescribed pattern response in the mainlobe peak direction is cast as a multi-convex problem at each step that the non-convex lower bound constraint is relaxed while including a reweighted l(1)-norm minimisation based on the magnitudes of the elements. Numerical tests, referred to benchmark problems, show that the proposed method achieves improved radiation performance by using fewer number of radiating elements.

Autocorrelation matching method is proposed for phase-only synthesis of power pattern of linear antenna arrays. This method is based on equating the autocorrelation coefficients of an array having given amplitude of excitations to those of a previously designed amplitude-phase array. Some examples are brought to verify the effectiveness of the proposed method for both pencil-beam and shaped beam patterns.

In this paper, we present two array response control algorithms for pattern synthesis with the aid of oblique projection. The proposed algorithms are developed on the basis of the weight vector orthogonal decomposition (WORD) approach, and both of them can control the array responses of multiple points starting from an arbitrarily given weight vector. They provide closed-form expressions and thus are computationally attractive and convenient to implement. Furthermore, for the preassigned angles to be controlled, the array responses can be adjusted flexibly and separately, and hence, the process of response control can be readily accomplished without complete recalculation, if some of the desired levels require adjustments. In addition, the second proposed algorithm modifies the first one and realizes the array response control without a beam axis shift. By successively performing the proposed algorithms to adjust the response to meet certain requirements, the array pattern can be synthesized. Extensive examples are provided to demonstrate the performances of the proposed algorithms in array response control and the effectiveness in pattern synthesis.

Pattern synthesis of Antenna array has gained much attention over the last years as they constitute an important role in the modern communication systems. Unit circle-based techniques such as Schelkunoff null placement method have proved their effectiveness to synthesize uniformly spaced linear arrays. Nonuniformly spaced antenna array pattern synthesis has been investigated and interesting results have been obtained. In this work, the unit circle representation approach is applied to synthesize nonuniformly spaced and nonuniformly excited linear arrays. The objective is to accurately place nulls in the desired directions while achieving the least possible sidelobe level. The problem is cast as an optimization problem that is solved using the Teaching Learning Based Optimization (TLBO). Examples are dealt with to prove the design approach effectiveness and flexibility for modern communication system applications.

In this paper, we propose an array pattern synthesis scheme using semidefinite programming (SDP) under array excitation power constraints. When an array pattern synthesis problem is formulated as an SDP problem, it is known that an additional rank‐one constraint is generated inevitably and relaxed via semidefinite relaxation. If the solution to the relaxed SDP problem is not of rank one, then conventional SDP‐based array pattern synthesis approaches fail to obtain optimal solutions because the additional rank‐one constraint is not handled appropriately. To overcome this drawback, we adopted a bisection technique combined with a penalty function method. Numerical applications are presented to demonstrate the validity of the proposed scheme.