scholarly journals Design of Uniform and Nonuniform Circular Arrays Comparison with FFA and RLS

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Dr Suraya Mubeen
Keyword(s):  
Communication Systems ◽  
Design Method ◽  
Beam Width ◽  
Side Lobe ◽  
Considerable Change ◽  
Base Stations ◽  
Side Lobe Level ◽  
Circular Aperture ◽  
Radio Communication ◽  
Circular Arrays

Multiple antennas can be arranged in various geometrical configurations to form antenna array with high directive radiation pattern. Linear antennas are limited in their steering capability. The circular arrays ar   more popular in recent years over other array geometries because they have the capability to perform the scan in all the directions and considerable change in the beam pattern which provide 3600 total coverage. Circular arrays are less sensitive to mutual coupling as compared to linear and rectangular arrays since they do not have edge elements. They can be used for beam forming in the azimuth plane for example at the base stations of the mobile radio communication systems as the components for signal processing. FFA design method of circular apertures for narrow beam width and low side lobes has been reported by Taylor. It includes the development of continuous circular aperture distributions, which contain only two independent parameters, A & , where A is related to the design of side lobe level and  is a number controlling the degree of uniformity of the side lobes.

Optimum design of linear and circular antenna arrays using equilibrium optimization algorithm

2021 ◽  
pp. 1-12
Author(s):  
Ali Durmus ◽  
Rifat Kurban
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Antenna Arrays ◽  
Optimization Algorithm ◽  
Communication Systems ◽  
Control Volume ◽  
Optimization Technique ◽  
Beam Width ◽  
Side Lobe ◽  
Side Lobe Level

Abstract In this paper, equilibrium optimization algorithm (EOA), which is a novel optimization algorithm, is applied to synthesize symmetrical linear antenna array and non-uniform circular antenna array (CAA). The main purpose of antenna array synthesis is to achieve a radiation pattern with low maximum side lobe level (MSL) and narrow half-power beam width (HPBW) in far-field. The low MSL here is an important parameter to reduce interference from other communication systems operating in the same frequency band. A narrow HPBW is needed to achieve high directionality in antenna radiation patterns. Entering the literature as a novel optimization technique, EOA optimally determined the amplitude and position values of the array elements to obtain a radiation pattern with a low MSL and narrow HPBW. The EOA is inspired by models of the control volume mass balance used to predict equilibrium as well as dynamic states. To demonstrate the flexibility and performance of the proposed algorithm, 10-element, 16-element and 24-element linear arrays and eight-element, 10-element and 12-element CAAs are synthesized. The MSL and HPBW values of radiation pattern obtained with the EOA are very successful compared to the results of other optimization methods in the literature.

scholarly journals Synthesis of Linear Array Antenna with Wide Range of beamwidths using DE Algorithm

2018 ◽  
Vol 7 (4.5) ◽  
pp. 273
Author(s):  
Challaram Grandhi ◽  
N. Grandhi1*, N.Venkateswara rao
Keyword(s):  
Communication Systems ◽  
Linear Array ◽  
Optimization Algorithms ◽  
Differential Evolution Algorithm ◽  
Beam Width ◽  
Side Lobe ◽  
Stochastic Methods ◽  
Side Lobe Level ◽  
De Algorithm ◽  
Wide Range

In many communication systems like Radar and point to point micro links there is a need of both narrow and wide beams. In target applications Antennas with narrow beam width is required on the other hand, for spy application antennas with wider beam width are required. Generally, for linear array antennas the beams width will be narrowed by increase in the number of elements in the array. To obtain narrow beams without a significant increase in the number of radiation elements in the array, the optimization algorithms are used. By the use of optimization algorithms the wider beams can also be employed in reverse procedure of choosing the highest output for a given set of random inputs. These wide ranges of beam width are obtained without any increase in the side lobe levels that is, by maintaining the side lobe level below -20db. Random stochastic methods like Particle swarm optimization (PSO), Genetic algorithm (GA), Biogeography-based optimization (BBO) and Differential Evolution Algorithm (DE) are used and the results are compared.  

Circular aerial arrays for radio astronomy

1961 ◽  
Vol 262 (1308) ◽  
pp. 84-99 ◽  
Keyword(s):  
Radio Astronomy ◽  
Side Lobe ◽  
Correction Function ◽  
Side Lobe Level ◽  
Circular Aperture ◽  
Circular Array ◽  
Polar Diagram ◽  
Beam Shape ◽  
Correction Process ◽  
Dimensional Distribution

A new type of aerial array suitable for high-resolution observations in radio astronomy is explored theoretically. The array consists of a large number of aerial elements equally Spaced round a circle and electrically connected in phase. The power polar diagram is calculated for the cases when the circle is effectively continuous, and when the separation between adjacent elements is appreciable. In both cases the side-lobe level is rather high for most radio astronomical purposes, for which a process of aerial correction is required. The function of the correction process is to readjust the relative weights of the different spatial Fourier components to provide a suitable beam shape. A general method of aerial correction is developed in which the two dimensional distribution of brightness directly recorded by scanning is cross-correlated with a circularly symmetrical correction function , a process which is desirably performed in the instrument itself. The correction process allows one to convert the polar diagram of a ring-shaped array into (for example) the diagram of a uniform circular aperture of the same radius. The principal theoretical characteristics of the circular array are briefly compared with those of the Mills cross. It is found that while the process of aerial correction or ‘tapering’ is technically more straightforward in the cross, the circular array has the following advantages: (1) the length of transmission line (and hence attenuation) between each element and receiver is halved; (2) the number of elements required to gain the same information is reduced, approximately in the ratio 4: π ; (3) the beam possesses circular or elliptical symmetry; and (4) the system offers the possibility of direct phase and amplitude calibration with the aid of a transmitter situated on a central tower.

scholarly journals Design and Analysis of Novel Fractal Linear and Planar Array Antennas for Satellite Applications

2016 ◽  
Vol 5 (3) ◽  
pp. 56 ◽  
Author(s):  
V. A. Sankar ◽  
P. V. Y. Jayasree
Keyword(s):  
Design Methodology ◽  
Beam Width ◽  
Side Lobe ◽  
Circular Ring ◽  
Geometric Design ◽  
Side Lobe Level ◽  
Array Antennas ◽  
Repetitive Nature ◽  
Satellite Applications ◽  
Planar Array

This article proposed a new geometric design methodology for the systematic expansion of fractal linear and planar array antennas. Using this proposed geometric design methodology any deterministic polygon shape can be constructed. In this article, two element fractal linear and triangular array antennas are examined using proposed methodology up to four iterations of two expansion factors. Due to the repetitive nature of the proposed geometric design methodology, both linear and planar fractal arrays shows multi-beam behavior with excellent array factor properties. The behavior of the proposed arrays shows better performance than linear and planar fractal array antennas generated by concentric circular ring sub array geometric generator. Triangular planar fractal array of expansion factor two at fourth iteration achieved a single valued beam width of 3.80 with -31.6 side lobe level. The suggested fractal arrays are analyzed and simulated by MATLAB-13 programming.

A Comparison of Swarm-Based Optimization Algorithms in Linear Antenna Array Synthesis

2021 ◽  
Author(s):  
Ali Durmus ◽  
Rifat KURBAN ◽  
Ercan KARAKOSE
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Antenna Arrays ◽  
Heuristic Algorithms ◽  
Beam Width ◽  
Side Lobe ◽  
Side Lobe Level ◽  
Linear Antenna ◽  
Half Power ◽  
Antenna Array Synthesis

Abstract Today, the design of antenna arrays is very important in providing effective and efficient wireless communication. The purpose of antenna array synthesis is to obtain a radiation pattern with low side lobe level (SLL) at a desired half power beam width (HPBW) in far-field. The amplitude and position values ​​of the array elements can be optimized to obtain a radiation pattern with suppressed SLLs. In this paper swarm-based meta-heuristic algorithms such as Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC), Mayfly algorithm (MA) and Jellyfish Search (JS) algorithms are compared to realize optimal design of linear antenna arrays. Extensive experiments are conducted on designing 10, 16, 24 and 32-element linear arrays by determining the amplitude and positions. Experiments are repeated 30 times due to the random nature of swarm-based optimizers and statistical results show that performance of the novel algorithms, MA and JS, are better than well-known methods PSO and ABC.

Performance Evaluation of Elliptical-Cylindrical Antenna Array using SaDE Optimized Hyper Beam

2017 ◽  
Vol 7 (1) ◽  
pp. 178 ◽  
Author(s):  
Gebrehiwet Gebrekrstos Lema
Keyword(s):  
Communication Systems ◽  
High Performance ◽  
Optimization Technique ◽  
Analytical Techniques ◽  
Side Lobe ◽  
Optimization Techniques ◽  
Side Lobe Level ◽  
Pattern Synthesis ◽  
Improved Performance ◽  
The Individual

<p>For high performance communication systems, Side Lobe Level (SLL) reduction and improved directivity are the goal of antenna designers. In the recent years, many optimization techniques of antenna design are occupying demanding place over the analytical techniques. Though they have contributed attractive solutions, it is often obvious to select one that meets the particular design need at hand. In this paper, an optimization technique called Self-adaptive Differential Evolution (SaDE) that can be able to learn and behave intelligently along with hyper beam forming is integrated to determine an optimal set of excitation weights in the design of EcAA. Non-uniform excitation weights of the individual array elements of EcAA are performed to obtain reduced SLL, high directivity and flexible radiation pattern. To evaluate the improved performance of the proposed SaDE optimized hyper beam, comparison are done with uniformly excited, SaDE without hyper beam and Genetic Algorithm (GA). In general, the proposed work of pattern synthesis has resulted in much better reduction of SLL and FNBW than both the uniformly excited and thinned EcAA. The results of this study clearly reveal that the SLL highly reduced at a very directive beamwidth.</p>

scholarly journals Design of Non-Uniformly Spaced Circular Arrays of Parasitic Dipoles for Lower Side Lobe Level with Maximum Directivity

2018 ◽  
Vol 7 (1) ◽  
pp. 51-56 ◽  
Author(s):  
H. Patidar ◽  
G. K. Mahanti
Keyword(s):  
Mutual Coupling ◽  
Side Lobe ◽  
Side Lobe Level ◽  
Circular Array ◽  
Method Of Moment ◽  
Lower Side ◽  
New Approach ◽  
Circular Arrays ◽  
Maximum Directivity ◽  
Active Dipole

This paper presents a new approach for circular array of parasitic dipoles composed by one active dipole for reduction of side lobe level with maximum directivity including mutual coupling. The desired goal is obtained by changing the spacing between the parasitic elements and length of the parasitic elements while the position and length of driven element is fixed. In addition to it, reflection coefficient (RC) of the driven element is kept closer to the specified value. Matlab based method of moment code is used to evaluate the performance of circular antenna designs generated by QPSO algorithm. Two examples are presented to show the effectiveness of this proposed approach.  

Sign in / Sign up

Export Citation Format

Share Document