Design of time modulated concentric circular and concentric hexagonal antenna array using hybrid enhanced particle swarm optimisation and differential evolution algorithm

• Published in: IET microwaves, antennas & propagation Vol. 8; no. 9; pp. 657 - 665
• Main Authors: Mangoud, Mohab A, Elragal, Hassan M, Alshara, Mohamed T
• Format: Journal Article
• Language: English
• Published: Stevenage The Institution of Engineering and Technology 01.06.2014; Institution of Engineering and Technology; The Institution of Engineering & Technology
• Subjects: antenna arrays; Antennas; Applied sciences; Arrays; CCA; CHA; Circuit properties; Circularity; concentric HA; concentric hexagonal antenna array; differential evolution algorithm; Directivity; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Exact sciences and technology; Excitation; hybrid enhanced particle swarm optimisation; hybrid EPSO‐DE optimisation technique; Hydroxyapatite; interelement spacing; Modulation; multiring concentric CA; Mutual coupling; Optimization; particle swarm optimisation; phase modulation; Radiocommunications; sidelobe level; SLL; Switching, multiplexing, switched capacity circuits; Telecommunications; Telecommunications and information theory; time modulated concentric circular antenna array; time modulated concentric circular antenna array; CCA; interelement spacing; particle swarm optimisation; hybrid enhanced particle swarm optimisation; sidelobe level; concentric hexagonal antenna array; hybrid EPSO-DE optimisation technique; SLL; differential evolution algorithm; antenna arrays; concentric HA; TM; CHA; multiring concentric CA; phase modulation; mutual coupling; Lateral lobe; Dynamic response; Mutual coupling; Evolutionary algorithm; Spacing; Particle swarm optimization; Directivity; Biomimetics; Modulation; Selector switch; Antenna array; Sideband; Rotation angle; Circular antenna
• ISSN: 1751-8725; 1751-8733; 1751-8733
• DOI: 10.1049/iet-map.2013.0132

Design of circular arrays (CAs) and hexagonal arrays (HAs) with low sidelobe level (SLL) and high directivity is usually achieved by increasing the number of array elements, which leads to a high undesired mutual coupling. Therefore this study presents an efficient optimisation method and a framework to show how to design multi-ring concentric CAs (CCA) and concentric HAs (CHAs) configurations using a hybrid enhanced particle swarm optimisation and differential evolution (hybrid EPSO/DE) optimisation technique. The presented optimum CCA and CHA have perfect invariant SLL and high directivity with low mutual coupling by keeping the inter-element spacing not less than half a wavelength which is not possible to be achieved in CA and HA arrangements. Different configurations with two-rings, three-rings and four-rings are presented. The rotation angle of outer rings and the complex excitations of array elements are first optimised. Then, this design is further optimised using a time modulation technique by controlling the switch-on times and the phases of elements excitations of the best CCA and CHA array designs. The presented time modulated (TM) concentric CA and TM concentric HA designs attain ultra-low SLL, reduced sideband level and maximised directivity besides reducing the dynamic range of the array excitations.