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19
Interference suppression of linear antenna arrays by amplitudeonly control using a bacterial foraging algorithm
 Progress In Electromagnetics Research, PIER 79
, 2008
"... Abstract—This paper presents a bacterial foraging algorithm (BFA) for null steering of linear antenna arrays by controlling only the element amplitudes. The BFA is a new evolutionary computing technique based on the foraging behavior of Escherichia (E.) coli bacteria in human intestine. To show the ..."
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Abstract—This paper presents a bacterial foraging algorithm (BFA) for null steering of linear antenna arrays by controlling only the element amplitudes. The BFA is a new evolutionary computing technique based on the foraging behavior of Escherichia (E.) coli bacteria in human intestine. To show the accuracy and flexibility of the proposed BFA, several examples of Chebyshev array pattern with the imposed single, multiple and broad nulls are given. It is found that the nulling method based on BFA is capable of steering the array nulls precisely to the undesired interference directions. 1.
Linear and circular array optimization: a study using particle swarm intelligence
 Progress In Electromagnetics Research B
, 2009
"... Abstract—Linear and circular arrays are optimized using the particle swarm optimization (PSO) method. Also, arrays of isotropic and cylindrical dipole elements are considered. The parameters of isotropic arrays are elements excitation amplitude, excitation phase and locations, while for dipole array ..."
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Abstract—Linear and circular arrays are optimized using the particle swarm optimization (PSO) method. Also, arrays of isotropic and cylindrical dipole elements are considered. The parameters of isotropic arrays are elements excitation amplitude, excitation phase and locations, while for dipole array the optimized parameters are elements excitation amplitude, excitation phase, location, and length. PSO is a highperformance stochastic evolutionary algorithm used to solve Ndimensional problems. The method of PSO is used to determine a set of parameters of antenna elements that provide the goal radiation pattern. The effectiveness of PSO for the design of antenna arrays is shown by means of numerical results. Comparison with other methods is made whenever possible. The results reveal that design of antenna arrays using the PSO method provides considerable enhancements compared with the uniform array and the synthesis obtained from other optimization techniques. 1.
Effect of mutual coupling and configuration of concentric circular array antenna on the signaltointerference performance
 in CDMA systems,” Progress In Electromagnetics Research, PIER
"... Abstract—The suitable use of an array antenna at the base station of a wireless communication system can result in improvement in signaltointerference ratio (SIR). In the present work, we consider circular array (CA) and concentric circular antenna array (CCAA) that are used for smart antenna syst ..."
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Abstract—The suitable use of an array antenna at the base station of a wireless communication system can result in improvement in signaltointerference ratio (SIR). In the present work, we consider circular array (CA) and concentric circular antenna array (CCAA) that are used for smart antenna systems. The performance criteria for SIR improvement is employed in this paper, is the spatial interference suppression coefficient. We first develop the expression of this figure of merit for CCAA and then analyze and compare the SIR performance for various configurations of eight and nine elements of CA and CCAA, with and without the element in the center by using circular patch antenna are provided. In addition, the effect of mutual coupling (MC) is taken into account. 1.
IMPROVED ADAPTIVE BACTERIA FORAGING ALGORITHM IN OPTIMIZATION OF ANTENNA ARRAY FOR FASTER CONVERGENCE
"... Abstract—This paper proposes an improved adaptive approach involving Bacterial Foraging Algorithm (BFA) to optimize both the amplitude and phase of the weights of a linear array of antennas for maximum array factor at any desired direction and nulls in specific directions. The Bacteria Foraging Algo ..."
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Cited by 7 (0 self)
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Abstract—This paper proposes an improved adaptive approach involving Bacterial Foraging Algorithm (BFA) to optimize both the amplitude and phase of the weights of a linear array of antennas for maximum array factor at any desired direction and nulls in specific directions. The Bacteria Foraging Algorithm is made adaptive using principle of adaptive delta modulation. To show the improvement in making the algorithm adaptive, results for both adaptive and nonadaptive algorithms are given. It is found that Adaptive Bacteria Foraging Algorithm (ABFA) is capable of improving the speed of convergence as well as the precision in the desired result. 1.
Pareto optimal YagiUda antenna design using multiobjective differential evolution
 Progress In Electromagnetics Research
"... Abstract—Antenna design problems often require the optimization of several conflicting objectives such as gain maximization, sidelobe level (SLL) reduction and input impedance matching. Multiobjective Evolutionary Algorithms (MOEAs) are suitable optimization techniques for solving such problems. An ..."
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Cited by 5 (0 self)
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Abstract—Antenna design problems often require the optimization of several conflicting objectives such as gain maximization, sidelobe level (SLL) reduction and input impedance matching. Multiobjective Evolutionary Algorithms (MOEAs) are suitable optimization techniques for solving such problems. An efficient algorithm is Generalized Differential Evolution (GDE3), which is a multiobjective extension of Differential Evolution (DE). The GDE3 algorithm can be applied to global optimization of any engineering problem with an arbitrary number of objective and constraint functions. Another popular MOEA is Nondominated Sorting Genetic AlgorithmII (NSGAII). Both GDE3 and NSGAII are applied to YagiUda antenna design under specified constraints. The numerical solver used for antenna parameters calculations is SuperNEC, an objectoriented version of the numerical electromagnetic code (NEC2). Three different YagiUda antenna designs are considered and optimized. Pareto fronts are produced for both algorithms. The results indicate the advantages of this approach and the applicability of this design method. 1.
EVALUATION OF A NEURALNETWORKBASED ADAPTIVE BEAMFORMING SCHEME WITH MAGNITUDEONLY CONSTRAINTS
"... Abstract—In this paper, we present an adaptive beamforming scheme for smart antenna arrays in the presence of several desired and interfering signals, and additive white Gaussian noise. As compared with standard schemes, the proposed algorithm minimizes the noise and interference contributions, but ..."
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Abstract—In this paper, we present an adaptive beamforming scheme for smart antenna arrays in the presence of several desired and interfering signals, and additive white Gaussian noise. As compared with standard schemes, the proposed algorithm minimizes the noise and interference contributions, but enforces magnitudeonly constraints, and exploits the arrayfactor phases in the desiredsignal directions as further optimization parameters. The arising nonlinearlyconstrained optimization problem is recast, via the Lagrange method, in the unconstrained optimization of a nonquadratic cost function, for which an iterative technique is proposed. The implementation via artificial neural networks is addressed, and results are compared with those obtained via standard schemes. 1.
Optimizing included angle of symmetrical Vdipoles for higher directivity using bacteria foraging optimization algorithm
 Progress In Electromagnetics Research B
"... Abstract—Recently the social foraging behavior of E. coli bacteria has been used to solve optimization problems. This paper presents an approach involving Bacterial Foraging (BF) to find appropriate included angle (ψ) and there by two other slant angles (θ1, θ2) for which the Vdipole provides highe ..."
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Abstract—Recently the social foraging behavior of E. coli bacteria has been used to solve optimization problems. This paper presents an approach involving Bacterial Foraging (BF) to find appropriate included angle (ψ) and there by two other slant angles (θ1, θ2) for which the Vdipole provides higher directivity in comparison to straight dipole. Symmetrical V and Straight dipole is analyzed completely using Method of Moments (MoM). MoM codes in MATLAB environment have been developed both for straight dipole and Vdipole to obtain impedance, directivity, and radiation patterns in both Eplane and Hplane. Then MoM codes is coupled with well known Bacteria Foraging Algorithm (BFA) to get best included angle. Moreover, some modification of BFA is done for the faster convergence. 296 Mangaraj, Misra, and Barisal 1.
A NOVEL ULTRAFAST ULTRASIMPLE ADAPTIVE BLIND BEAMFORMING ALGORITHM FOR SMART ANTENNA ARRAYS
"... Abstract—This research proposes a new blind tracking algorithm for smart antenna arrays by switching the main beam iteratively using the cost calculated from the received and predicted symbol. This algorithm will be called Cost Steering Algorithm Using DemodulationRemodulation Technique COSTAUS/DRT ..."
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Abstract—This research proposes a new blind tracking algorithm for smart antenna arrays by switching the main beam iteratively using the cost calculated from the received and predicted symbol. This algorithm will be called Cost Steering Algorithm Using DemodulationRemodulation Technique COSTAUS/DRT. It is completely independent of the Least Mean Squares (LMS) or any derived version from it, and it does not need to investigate the cyclostationary properties of the incoming signal. A complete derivation and analytical model with simulation using Simulink is given in this research. The algorithm was tested under three different target motions which are a triangular motion (linear), sinusoidal motion (circular) and saw tooth motion which is an adverse case when the linear motion changes its path suddenly. The transmitter uses 16level PSK signal with no Forward Error Correction code (FEC) in order to test the algorithm under the worst situation. The algorithm is tested under different noise power levels. The antenna array is a linear array with 16elements. 1.
LOW RCS DIPOLE ARRAY SYNTHESIS BASED ON MOMPSO HYBRID ALGORITHM
"... Abstract—In this paper, a hybrid algorithm combined method of moments (MoM) with particle swarm optimization (PSO) is used to realize low radar cross section (RCS) array synthesis. Both the scattering factor and the radiation factor are involved in the proposed objective function to achieve the prom ..."
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Abstract—In this paper, a hybrid algorithm combined method of moments (MoM) with particle swarm optimization (PSO) is used to realize low radar cross section (RCS) array synthesis. Both the scattering factor and the radiation factor are involved in the proposed objective function to achieve the promising dipole array with a reduced RCS and satisfied radiation performance. To improve the optimization efficiency, radiation constraint conditions are adopted to avoid unnecessary scattering calculation. The symmetric matrix and block treatment are also used to fill the MoM impedance matrix. The optimization results show that the proposed algorithm is able to achieve RCS reduction of 5.5 dB for dipole array. 1.
Concentric circular array antenna null steering synthesis by using modified hybrid ant colony system algorithm”, Int
 Page  124 Journal of Enhanced Research in Science Technology & Engineering, ISSN: 23197463
, 2010
"... In this article, a hybrid optimization method has been proposed consisting of modified ant colony systems (ACSs) and constrained nonlinear programming (NLP) to solve the problems of null synthesis of concentric rings circular array antenna consist of parallel center feeding dipoles elements with two ..."
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In this article, a hybrid optimization method has been proposed consisting of modified ant colony systems (ACSs) and constrained nonlinear programming (NLP) to solve the problems of null synthesis of concentric rings circular array antenna consist of parallel center feeding dipoles elements with two complex nonlinear optimization problems. In the first problem, a synthesis of concentric circular array radiation pattern with many interface signals is considered. In the second problem, the hybrid optimization algorithm is used to achieve wide nulls in the concentric circular array radiation pattern. The optimization process is achieved by finding the optimal values of the excitation coefficients of each element in the circular rings array. Several examples are considered here to verify the validity of this method. The results obtained by this method show that it is possible to obtain an array radiation pattern with wide null width of 90 o with a depth equal to60dB and two nulls on both sides of the main lobe with about112.9 dB depth level. Comparisons were made between the results of this proposed method and the results obtained by many other evolutionary optimization algorithms, and it is clearly shown that this method is more efficient and flexible in solving the problems of concentric circular array antenna performance optimization.