%0 Journal Article
%T QPSO versus BSA for Failure Correction of Linear Array of Mutually Coupled Parallel Dipole Antennas with Fixed Side Lobe Level and VSWR
%A R. Muralidharan
%A Vallavaraj Athinarayanan
%A G. K. Mahanti
%A Ananya Mahanti
%J Advances in Electrical Engineering
%D 2014
%R 10.1155/2014/858290
%X Evolutionary algorithms play an important role in synthesizing linear array antenna. In this paper, the authors have compared quantum particle swarm optimization (QPSO) and backtracking search algorithms (BSA) in failure correction of linear antenna arrays constructed using half wavelength uniformly spaced dipoles. The QPSO algorithm is a combination of classical PSO and quantum mechanics principles to enhance the performance of PSO and BSA is considered as a modernized PSO using historical populations. These two algorithms are applied to obtain the voltage excitations of the nondefective elements in the failed antenna array such that the necessary objectives, namely, the minimization of parameters like side lobe level (SLL) and voltage standing wave ratio (VSWR), are achieved leading to their values matching closely the desired parameter values. The results of both algorithms are compared in terms of parameters used in the objective function along their statistical parameters. Moreover, in order to reduce the processing time, inverse fast Fourier transform (IFFT) is used to obtain the array factor. In this paper, an example is presented for the application of the above two algorithms for a linear array of 30 parallel half wavelength dipole antennas failed with 4 elements and they clearly show the effectiveness of both the QPSO and BSA algorithms in terms of optimized parameters, statistical values, and processing time. 1. Introduction Any failure in the elements of the antenna array [1] will end up in corruption of radiation pattern and lead to deviation of the radiation pattern parameters, namely, side lobe level, first null beam width (FNBW), half power beam width (HPBW), and so forth, thus leading to degradation in the performance of the communication systems. Researches in the past have clearly depicted various ways of recovery [2¨C4]. A simple way to recover the radiation pattern is to manually replace the failed antenna elements, which is not quite a better solution when the deformation occurs in applications like satellites, radar, and so forth. Literature survey has revealed that the idea of adjusting the beam weights of the remaining nondefective elements in the array results in production of radiation pattern approaching the original pattern in terms of the radiation pattern parameters being extensively used. Mailloux [2] utilized the idea of replacing the signals in a digitally beam formed array in a multiple Signal environment without laying any restrictions on correlation properties of signals. A method [3] based on evolutionary algorithm,
%U http://www.hindawi.com/journals/aee/2014/858290/