Pattern Synthesis of Planar Nonuniform Circular Antenna Arrays Using a Chaotic Adaptive Invasive Weed Optimization Algorithm

Abstract

A novel invasive weed optimization (IWO) variant called chaotic adaptive invasive weed optimization (CAIWO) is proposed and applied for the optimization of nonuniform circular antenna arrays. A chaotic search method has been combined into the modified IWO with adaptive dispersion, where the seeds produced by a weed are dispersed in the search space with standard deviation specified by the fitness value of the weed. To evaluate the performance of CAIWO, several representative benchmark functions are minimized using various optimization algorithms. Numerical results demonstrate that the proposed approach improves the performance of the algorithm significantly, in terms of both the convergence speed and exploration ability. Moreover, the scheme of CAIWO is employed to find out an optimal set of weights and antenna element separation to obtain a radiation pattern with maximum side-lobe level (SLL) reduction with different numbers of antenna element under two cases with different purposes. The design results obtained by CAIWO have comfortably outperformed the published results obtained by other state-of-the-art metaheuristics in a statistically meaningful way.

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

“…The proposed technique is different from [4][5][6][7][8][9][10][11] in the sense that the authors here considered the length of parasitic elements and spacing between the parasitic elements as design variables to obtain the desired requirements keeping the position and length of active element fixed. Moreover, this technique is different from [4][5][6][7][8][9][10][11] in the sense that authors here considered real antennas including mutual coupling effect. In addition to it, coupling effect is also compensated by minimizing the reflection coefficient of the driven element to the specified value.…”

“…In recent years circular arrays have become more in demand over other array geometries because of circular arrays have the potential to perform the scan in all the directions without a significant change in the beam pattern and provides azimuth coverage of 360 0 [4][5][6][7][8][9][10][11]. Many researchers presented approaches for reduction of side lobe level with fixed beam width in circular antenna arrays by changing the excitation amplitudes and spacing between the elements [4][5][6][7][8][9][10]. Synthesis of circular antenna arrays with low side lobe level under both no beam scanning and beam scanning conditions using amplitude only and amplitude spacing are detailed in [11].…”

Chaotic Adaptive Butterfly Mating Optimization and Its Applications in Synthesis and Structure Optimization of Antenna Arrays

“…Singh and Salgotra [10] applied an enhanced flower pollination algorithm to a linear antenna array (LAA) for the pattern synthesis with sidelobe level (SLL) suppression and null control. Wu et al [11] proposed a chaotic adaptive invasive weed optimization (CAIWO) to synthesize the planar nonuniform circular arrays and compared it with a genetic algorithm (GA) [12] and particle swarm optimization (PSO) [13,14]. Panduro et al [15] applied an evolutionary algorithm (EA) to design the steerable linear arrays.…”

Synthesis of circular arrays with sidelobes of individually arbitrary levels

“…A conventional approach to synthesize the circular arrays is using optimization techniques. Many kinds of optimization techniques such as invasive weed, genetic algorithm, particle swarm have been presented to find the optimum positions of the antennas. Both amplitude and/or phase of the antennas may also be considered as the unknown parameters to synthesize the radiation pattern of circular arrays …”

“…The position of the antennas may be changed in radial 2 or angular [3][4][5][6][7] directions. A conventional approach to synthesize the circular arrays is using optimization techniques.…”