Abstract-Circular antenna array design is one of the most important electromagnetic optimization problems of current interest.The problem of designing a large multiple concentric planar thinned circular ring arrays of uniformly excited isotropic antennas is considered in this paper. This antenna must generate a pencil beam pattern in the vertical plane along with minimized side lobe level (SLL). In this paper, we present an optimization method based on an improved variant of one of the most powerful real parameter optimizers of current interest, called Differential Evolution (DE). Two sets of different cases have been studied here. First set deals with thinned array design with the goal to achieve number of switched off elements equal to 220 or more. The other set contains design of array while maintaining side lobe level (SLL) below a fixed value. Both set contains two types of design, one with uniform inter-element spacing fixed at 0.5λ and the other with optimum uniform inter-element spacing. The half-power beam width of the synthesized pattern is attempted to maintain fixed at the value equal to that of a fully populated array with uniform spacing of 0.5λ. Simulation results of the designed thinned arrays are compared with a fully populated array for all the cases to illustrate the effectiveness of our proposed method.
Abstract-Our main objective in this article is to achieve minimum side lobe levels for a specific first null beam-width and also a minimum size of the circumference by an optimization-based design method for non-uniform, planar, and circular antenna arrays.
This paper proposes an improved and adaptive variant of the differential evolution algorithm for the design of twochannel quadrature mirror filters with linear phase characteristics. To match the ideal system response characteristics, the algorithm is employed to optimize the values of the filter bank coefficients. The filter response is optimized in both passband and stopband. The overall filter bank response aims at minimizing objectives like reconstruction error, mean square error in passband, and mean square error in stopband. Effective designing can be achieved by efficiently minimizing the objective function. The proposed algorithm is able to perform better than the other existing design methods. Five different design examples are presented to validate the effectiveness of the proposed approach over other conventional design techniques, as well as state-of-the-art evolutionary algorithms found in the literature.Index Terms-Differential evolution (DE), filter banks, perfect reconstruction, quadrature mirror filter (QMF), sub-band coding.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.