Radiation Pattern Of Antenna Array Research Articles

An optimal concentric circular antenna array design using atomic orbital search for communication systems

Abstract In this study, optimum radiation patterns of Concentric Circular Antenna Arrays (CCAAs) are obtained by using the Atomic Orbital Search (AOS) algorithm for communication spectrum. Communication systems stands as a nascent technological innovation poised to revolutionize the landscape of wireless communication systems. It distinguishes itself through its hallmark features, notably an exceptionally high data transmission rate, expanded network capacity, minimal latency, and a commendable quality of service. The most important issue in wireless communication is a precision antenna array design. The success of this design depends on suppressing the maximum sidelobe levels (MSLs) values of the antenna in the far-field radiation region as much as possible. The AOS, which is a rapid and flexible search algorithm, is a novel physics-based algorithm. The amplitudes and inter-element spacing of CCAAs are optimally determined by utilizing AOS to the reduction of the MSLs. In this study, CCAAs with three and four rings are considered. The number of elements of these CCAAs has been determined as 4–6–8, 8–10–12 and 6–12–18–24. The radiation patterns obtained with AOS are compared with the results available in the literature and it is seen that the results of the AOS method are better.

Synthesis of Antenna Array Radiation Pattern at Large Scanning Angles Using Genetic Algorithm

At present, in most modern communication systems, for example, in modern satellite terminals, the use of scanning beam antennas, i. e. antenna arrays is assumed. At the same time, at large scanning angles, the side lobe level (SLL) increases strongly and decrease in the gain is observed. In this regard, the problem of finding a procedure for synthesizing an amplitude-phase distribution (APD) with low SLL and high gain (G) at large scanning angles comes up. One of the ways to reduce SLL and compensate for the decrease in G is to synthesize the optimal APD (in terms of the maximum G and minimum SLL) using optimization algorithms. At the same time, taking into account the characteristics of the radiation pattern of the array emitters requires numerical electrodynamic calculation. The goal of this paper is to develop a procedure for the synthesis of APD with low SLL for linear and rectangular antenna arrays at various, including large, scanning angles and compensation for G reduction using a genetic algorithm and numerical electrodynamic calculation. The methods for studying the characteristics of antenna radiators are numerical electrodynamic modeling by the finite element method (FEM) in Ansys HFSS computer-aided design system and optimization of the APD for a given radiation pattern(RP) by a random search method using partial diagrams of antenna elements. The novelty is the combination of accurate numerical electrodynamic calculation of the RP of antenna elements and optimization search for APD for the synthesis of the required RP using partial diagrams. As a result, a procedure for APD synthesis of linear and uniform rectangular equidistant (for example, 8- and 64-element) antenna arrays has been developed, taking into account the exact electrodynamic characteristics of antenna elements and their mutual resistance. Radiation patterns were obtained taking into account the effect of neighboring elements, with the help of which, using a genetic algorithm, APDs on emitters were found at different scanning angles. The change in SLL and G of the antenna array is analyzed at different scanning angles using different APDs. The proposed algorithm allows to synthesize APD for a RP with low SLL and high G at scanning angles up to 40° for linear antenna array and up to 80° in the case of a uniform rectangular antenna array. The results of this work are relevant in the problems of radiation pattern synthesis, since the proposed solution provides a significant gain in the radiation pattern synthesis rate of APD of linear and rectangular antenna arrays, especially for systems with a large number of antenna elements. At the same time, it is possible to maintain a high G at large scanning angles, and achieve a significant reduction of SLL.

Synthesis of a steerable frequency-invariant radiation pattern for broadband scalable antenna arrays

This paper discusses the synthesis of a steerable frequency-invariant radiation pattern for broadband scalable antenna arrays (SAAs). The proposed method allows to achieve constant beamwidth and beam direction over a 3:1 bandwidth and is based on an appropriate radiating elements’ placement in the SAA and a proper amplitude and phase excitation of the array. Both amplitudes and phases of signals exciting the radiating elements are varied with frequency to ensure the radiation pattern invariance. Additionally, the paper proposes solutions to problems occurring in SAAs i.e., the problem of overlapping radiating elements and the problems of sidelobe and grating lobe reduction. To verify the proposed synthesis method, a set of radiating elements, which operate over a 3−9 GHz frequency range, has been manufactured and measured. The overall radiation pattern of the antenna array has been obtained by a summation of the radiation patterns produced by each of the radiating elements.

Investigation of Bilateral Skeletonization Technique in Fast Computation of Receiving Radiation Pattern for Radome-Enclosed Antenna Arrays

Investigation of Bilateral Skeletonization Technique in Fast Computation of Receiving Radiation Pattern for Radome-Enclosed Antenna Arrays

A Wild Horse Optimization algorithm with chaotic inertia weights and its application in linear antenna array synthesis.

Antennas play a crucial role in designing an efficient communication system. However, reducing the maximum sidelobe level (SLL) of the beam pattern is a crucial challenge in antenna arrays. Pattern synthesis in smart antennas is a major area of research because of its widespread application across various radar and communication systems. This paper presents an effective technique to minimize the SLL and thus improve the radiation pattern of the linear antenna array (LAA) using the chaotic inertia-weighted Wild Horse optimization (IERWHO) algorithm. The wild horse optimizer (WHO) is a new metaheuristic algorithm based on the social behavior of wild horses. The IERWHO algorithm is an improved Wild Horse optimization (WHO) algorithm that combines the concepts of chaotic sequence factor, nonlinear factor, and inertia weights factor. In this paper, the method is applied for the first time in antenna array synthesis by optimizing parameters such as inter-element spacing and excitation to minimize the SLL while keeping other constraints within the boundary limits, while ensuring that the performance is not affected. For performance evaluation, the simulation tests include 12 benchmark test functions and 12 test functions to verify the effectiveness of the improvement strategies. According to the encouraging research results in this paper, the IERWHO algorithm proposed has a place in the field of optimization.

Overview of algorithms for approximation of the electromagnetic field and synthesis of antenna array radiation patterns

Overview of algorithms for approximation of the electromagnetic field and synthesis of antenna array radiation patterns

A High-Efficient Method for Synthesizing Multiple Antenna Array Radiation Patterns Simultaneously Based on Convolutional Neural Network

This paper proposes a high-efficient method that utilizes deep learning technology for synthesizing multiple antenna array radiation patterns simultaneously. More in details, the mathematical feasibility of using neural networks to optimize and synthesize radiation patterns of antenna arrays is demonstrated. Boundary functions are designed to reshape the important characteristics of target radiation patterns and transform them into a two-channel mask matrix, allowing for the simultaneous input of multiple target radiation patterns into the neural network without sacrificing computational efficiency. During training, the cost function is designed to represent the difference between each synthesized radiation pattern and the corresponding target radiation pattern, guiding self-learning. The main framework of the method is a convolutional neural network, where the convolutional layer is used to reduce the expansion of input parameters due to the simultaneous input of multiple mask matrices. Simulation experiments have been conducted to synthesize multiple incoherent target radiation patterns simultaneously on a patch antenna array layout, and the computation time is compared with the combined time required to compute each one individually. The results demonstrate that this method offers the advantage of computational efficiency for simultaneous synthesis of multiple incoherent radiation patterns.

The processing method of the parameters of the beam pattern of phased array antennas

The investigation results of the radiation pattern as one of the important parameters of the phased array antenna are presented at the article. Practical results: obtaining skills in using MathCad and researching methods for improving the directional pattern in order to increase the accuracy of determining the goal. The paper presents an algorithm for calculating the radiation pattern of antenna arrays with four modules and a method for improving it. Software and mathematical results are available in the Internet for free, that allows anyone to do similar work to confirm the calculations and conclusions. The results could be used at students practice in technical universities while studying in specialties related to radio electronic engineering in courses connected with study of the design principles of antenna systems with an equidistant arrangement of elements. Publication could be recommended as methodical manual to students for homework solving or laboratory work using specialized MathCad software.

Generation of 3D quasi-spherical multi-focus arrays and optical rings using orthogonally superimposed dipole antenna arrays

This paper proposes a novel method to generate a three-dimensional (3D) quasi-spherical focal point with high longitudinal and transverse resolution in a 4Pi focusing system based on the radiation pattern of the orthogonally superimposed dipole antenna. In this paper, we present generated 3D quasi-spherical multi-focus arrays that are controllable and uniformly distributed and optical rings from the radiation patterns of antenna arrays in different configurations. The results showed that the generated focal point is smaller longitudinally (0.31λ) than transversely (0.41λ). This focal point has the smallest volume (∼0.0273λ 3) found. Moreover, it is highly homogeneous and has a small side lobe. The polarization at the center of the focal point is purely circular. The resulting 3D focal fields can be easily tailored by adjusting the modulation parameters of the orthogonally superimposed dipole arrays. Manipulating 3D optical focal fields with pre-defined characteristics of quasi-spherical focal points has a high degree of freedom. Many potential applications exist in arbitrarily oriented particle capture and guidance, micromanipulation, optical capture, and 3D optical data storage.

МЕТОД ПОДАВЛЕНИЯ ИМПУЛЬСНЫХ ПОМЕХ В АДАПТИВНОЙ АНТЕННОЙ РЕШЕТКЕ С ЛОГИЧЕСКОЙ ОБРАБОТКОЙ СИГНАЛОВ

A method for suppressing pulse interference in adaptive antenna arrays is proposed, characterized by the use of a procedure for logical signal processing in the main and compensation channels to form a covariance interference matrix. To form the directional pattern of the main channel, weight coefficients are used to ensure a low level of side lobes. The radiation pattern of the compensation channel is obtained by subtracting the radiation patterns of orthogonal linear antenna arrays highlighted in the opening of the antenna array. Logical processing is used to determine the time domain, which does not contain a signal component, but contains external interference. It is shown that the use of logical processing of the main and compensation channels ensures the exclusion of the signal component from the covariance interference matrix and increases the noise immunity of the antenna.

Beamforming Network Design Utilizing Node Microstrip Architectures for Dual-Polarized Endfire Millimeter-Wave Antenna Arrays

A node microstrip architecture is proposed for designing a compact Butler Matrix (BM) that is integrated with a dual-polarized endfire antenna array. The node microstrip architecture can be used to form a variety of compact 2 × 2 port networks including, but not limited to, couplers and crossovers. By concatenating the 2 × 2 port networks together, a compact BM with any number of ports can be formed. Using the proposed method, a compact 4 × 4 port BM operating in the millimeter wave band is designed and integrated with a dual-polarized endfire antenna array. The size of the compact BM is 2.1λ × 2λ and the size of the whole dual-polarized endfire antenna array with BM is 2.6λ × 4.8λ, which is smaller than traditional structures. The measured radiation pattern of the dual-polarized antenna array can achieve beam-scanning up to ±38° in the azimuth plane. The two beams in the dual-polarized endfire antenna array can also be independently steered. The optimized compact BM is potentially suitable for use in 5G wireless communication handsets.

Effect of Locally Flat Distortions in the Radiating Aperture on the Radiation Pattern of a Phased Antenna Array

Introduction. Phased antenna arrays (PAA) of large geometric dimensions find wide application in various spacecraft systems. The PAA design assumes the deployment of its sections in outer space to form a plane of the radiating aperture. However, when implementing such a design, locally flat violations of the radiating aperture may occur. In turn, this may lead to distortion of the original amplitude and phase distribution (APD) under the correct antenna deployment. As a result, the shape of the radiation pattern (RP) changes, in particular, its main maximum shifts and the level of side lobes increases. Under these conditions, in order to ensure the formation of a pattern with the given parameters, it is necessary to correct the APD in a PAA.Aim. To develop a method for correcting the APD in a PAA under the known parameters of violations in the radiating aperture geometry.Materials and methods. The method is based on the condition of minimizing the root-mean-square deviation of the RP formed after correction from the original RP in the absence of aperture violations. The basis of the method is the formation of a redefined system of linear algebraic equations (SLAE) connecting the parameters of geometry violations with RP distortions. Each of the SLAE equations corresponds to a certain angular direction in space, in which the condition of coincidence of the original and corrected RP is imposed.Results. A method for correcting the APD in the presence of locally flat violations of the PAA radiating aperture is proposed. Numerical simulation of the relationship between the parameters of violations and the directional characteristics was carried out. The main relations and results of numerical simulation are presented, in particular, the amplitude distributions, as well as the cross sections of the formed RP and the difference of the normalized RP in the presence of errors in the deployment of the PAA web both without and with APD correction.Conclusion. The results obtained show that, in the absence of APD correction in the PAA aperture, the formation of RP with the given parameters cannot be ensured. In particular, there is a shift of the main maximum of the RP and a change in the nature of the envelope of the side lobes. At the same time, APD correction makes it possible to maintain the RP practically unchanged.

Design Optimization for UAV Aided Sustainable 3D Wireless Communication at mmWaves

Unmanned aerial vehicles (UAVs) operating at different altitudes will be integral to the 5th generation and beyond (5G+) communication network to provide ubiquitous coverage. Though 5G+ communications target to operate in sub-6 GHz as well as millimeter wave range (mmWaves), sub-6 GHz being already congested, mmWaves are seen as a viable technology that can support high data rates. To this end, in this paper, we study the feasibility of using UAVs at mmWaves deployed at low altitudes to serve a user population higher than the number of RF chains available at the UAV. Since the UAVs are energy constrained devices, solar harvesting is considered for the UAVs to act as access nodes for an extended period of time. Practical 3-dimensional antenna array radiation pattern and the resulting inter-beam interference from the sidelobes are taken into account in the analysis. We devise a sub-array hybrid precoder that provides minimum rate support to all users across the wideband mmWave channel. The RF precoder is designed according to the users' locations. In addition, we propose a low complexity iterative joint subcarrier allocation and baseband precoder optimization algorithm with faster convergence. In the proposed algorithm, we employ weighted minimum mean squared error (WMMSE) to design baseband precoder to reduce inter-beam interference while jointly optimizing subcarrier allocation to maintain minimum user rate constraint. Next, we determine the optimal number of beams at UAV to optimize throughput while guaranteeing minimum user rate support for energy sustainable UAV operation. Finally, we compare the performance gain achieved by low-altitude UAV deployed at mmWaves over the UAV deployed at sub-6 GHz frequency range.

Design and analysis of microstrip transceiver array antennas with the function to suppress beam deflection for 77 GHz automotive radar

A microstrip transceiver array antenna with high beam pointing accuracy is designed for automotive radar. Considering the influence of the lossy conductor on the excitation current, the beam deflection problem formed by the passive microstrip series-feed linear array is analyzed and solved. Compared with the traditional microstrip series-feed linear array, the microstrip series feeder array designed in this paper has good beam pointing accuracy. A power divider based on substrate-integrated waveguide (SIW) and microstrip line (MSL) with Chebyshev amplitude distribution(applied to the transmit array antenna) and binomial amplitude distribution(applied to the receive array antenna), respectively, is designed as the feeding network of the linear array. The fabrication and measurement of the prototype transceiver array antenna are completed to verify its beam directivity. The simulation and measurement results show that the E-plane main beam of the transceiver array antenna radiation pattern has good pointing accuracy, which makes the detection accuracy of the automotive radar significantly improved.

Conflicting Parameter Pair Optimization for Linear Aperiodic Antenna Array using Chebyshev Taper based Genetic Algorithm

In this study, the peak side lobe level (PSLL) in the radiation pattern of a linear antenna array (LAA) is lowered without affecting its first null beam width (FNBW). Antenna array synthesis is commonly applied to achieve high directivity, low side lobes, high gain and desired null positions in the output radiation pattern. But output parameters like PSLL, null positions and beam width conflict with each other, i.e. as one parameter improves, the other deteriorates. To avoid this problem, a multi-objective optimization algorithm can be implemented, in which both the conflicting parameters can be simultaneously optimized. This work proposes a multi-objective algorithm, which takes advantages of the well-known Chebyshev tapering and genetic algorithm (GA), to lower the PSLL without broadening the beam further. Array elements are fed using Chebyshev tapered excitations while GA is incorporated to optimize the elemental spacing. The results of 28-element LAA are compared with those of multi-objective Cauchy mutated cat swarm optimization (MO-CMCSO) existing in literature, which has also been proven to be superior to multi-objective cat swarm optimization (MO-CSO) and multi-objective particle swarm optimization (MO-PSO). Results indicate that the proposed algorithm performs better by further reducing the PSLL from -21.57 dB (MO-CMCSO) to -28.18 dB, while maintaining the same FNBW of 7.4 degrees.

The processing method of the parameters of the beam pattern of phased array antennas

The investigation results of the radiation pattern as one of the important parameters of the phased array antenna are presented at the article. Practical results: obtaining skills in using MathCad and researching methods for improving the directional pattern in order to increase the accuracy of determining the goal. The paper presents an algorithm for calculating the radiation pattern of antenna arrays with four modules and a method for improving it. Software and mathematical results are available in the Internet for free, that allows anyone to do similar work to confirm the calculations and conclusions. The results could be used at students practice in technical universities while studying in specialties related to radio electronic engineering in courses connected with study of the design principles of antenna systems with an equidistant arrangement of elements. Publication could be recommended as methodical manual to students for homework solving or laboratory work using specialized MathCad software.

Efficient Radiation Pattern Prediction of Array Antennas Based on Complex-Valued Graph Neural Networks

Antenna design with the traditional numerical methods is a highly computationally expensive task. In this letter, a complex-valued graph neural network (GNN) with residual connections is proposed to efficiently predict radiation pattern for antenna arrays with different geometric structures. The model uses GNN as a backbone, and the topological structure and excitation of the antenna array are encoded into a graph representation. Complex weights and residual connections are designed to improve the accuracy of the model. Experiments are conducted on five kinds of arrays under amplitude–phase control. The experimental results show that the average mean absolute percentage error and the average root-mean-square error of the model on five types of the antenna array are 1.86% and 0.032, respectively, while the time efficiency of the model is six orders of magnitude faster than that of the traditional full-wave simulation.

Arrays of combined antennas with equal-amplitude distribution of bipolar voltage pulses

The paper presents the comparative characteristics of the radiation pattern of the combined antenna arrays excited by a bipolar pulse and harmonic oscillations near the central frequency of the spectrum of ultrawideband radiation. Particular attention is paid to the 3x3 array radiation source with maximum efficiency.

Antenna array control system with combination of strength and flexible scanning programs

The structure of the antenna array control system with a combination of strengh and flexible scanning programs is proposed, characterized by the introduction of additional modules of statistics and expert assessments in the feedback circuit between the secondary processing module and hardware and software complexes for the formation of transmitting and receiving antenna array radiation patterns. The implementation of this structure allows for the formation of an additional transmitting and several receiving beams to confirm marks that do not meet the specified detection criterion. An algorithm for controlling an active phased array antenna has been developed, characterized by a procedure for additional confirmation of marks with a low signal-to-noise ratio due to the formation of additional transmitting and receiving beams. The estimates of the gain from the implementation of the proposed structural scheme of the antenna array control system and the algorithm of its functioning are obtained.

High‐efficient optimisation method of antenna array radiation pattern synthesis based on multi‐layer perceptron network

With the increasing complexity of the application environment of antenna arrays and the increasing requirements for antenna array radiation patterns, efficient optimisation methods of antenna array radiation pattern synthesis have always been the challenges of the research. This paper proposes a method of utilising a multi-layer perceptron network to optimise the radiation patterns of antenna array. The optimisation requirements of the antenna array radiation pattern are described by defining the objective mask function, which is designed to shape the target radiation pattern by desired features. Simulation experiments have been designed with a variety of antenna array layouts, of which the radiation patterns with different requirements were successfully synthesised and optimised. The results show that the proposed method has high efficiency and satisfactory optimisation effect in dealing with the problem of complex radiation pattern requirements.