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The applications of a hybrid real-binary particle swarm optimization (HPSO) algorithm in engineering electromagnetics are described. In HPSO, each candidate design is designated by a hybridized vector consisting of both real and binary variables. These variables are evolved in the optimization by following the velocity/position updating formulas of real-number PSO (RPSO) and binary PSO (BPSO), respectively. Both single- and multi-objective implementations of the algorithm are validated by functional testbeds. Simulation and measurement results of three examples, i.e, the design of a non-uniform antenna array, a multilayered planar radar absorbing material (RAM) and a dual-band handset antenna are presented, in order to illustrate the effectiveness of the algorithm in representative topology exploration and material selection problems. [ABSTRACT FROM AUTHOR]

A novel design methodology is presented for correlator antenna arrays in radio astronomy applications. In order to characterize the spatial-filter-like performance of a correlator array, an analyzer is developed to calculate its u-v coverage and synthesized beam, along with the capability to simulate the Earth rotation effect and the image retrieval process. On the other hand, particle swarm optimization (PSO) is applied to determine the locations of antenna elements in typical open-ended and closed array configurations (such as the "Y" and the Reuleaux triangle), in order to achieve either the maximum u-v coverage or a synthesized beam with the lowest sidelobe level (SLL). Optimized arrays are observed to outperform uniform arrays and representative existing designs. [ABSTRACT FROM AUTHOR]

This paper presents a novel evolutionary optimization methodology for multiband and wide-band patch antenna designs. The particle swarm optimization (PSO) and the finite-difference time-domain (FDTD) are combined to achieve the optimum antenna satisfying a certain design criterion. The antenna geometric parameters are extracted to be optimized by PSO, and a fitness function is evaluated by FDTD simulations to represent the performance of each candidate design. The optimization process is implemented on parallel clusters to reduce the computational time introduced by full-wave analysis. Two examples are investigated in the paper: first, the design of rectangular patch antennas is presented as a test of the parallel PSO/FDTD algorithm. The optimizer is then applied to design E-shaped patch antennas. It is observed that by using different fitness functions, both dual-frequency and wide-band antennas with desired performance are obtained by the optimization. The optimized E-shaped patch antennas are analyzed, fabricated, and measured to validate the robustness of the algorithm. The measured less than — 18 dB return loss (for dual-frequency antenna) and 30.5% bandwidth (for wide-band antenna) exhibit the prospect of the parallel PSO/FDTD algorithm in practical patch antenna designs. [ABSTRACT FROM AUTHOR]