Title :
Full-polarisation three-dimensional pattern synthesis for conformal conical arrays with dynamic range ratio constraint by using the initialisations based on equivalence theorem
Author :
Yunxiang Zhang ; Zhiqin Zhao ; Zaiping Nie ; Qing Huo Liu
Author_Institution :
Sch. of Electron. Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
To design three-dimensional (3D) conformal conical arrays with desired 3D co-polarisation and cross-polarisation radiation patterns, a pattern synthesis method based on equivalent principle and trust region method is presented. Dynamic range ratio (DRR) of element excitations is taken into consideration. An analytical function is utilised to constrain DRR and avoid discontinuity of objective function. Owing to the optimisation is based on very good initial currents distribution, the optimisation procedure is very fast. The analytical gradient and Hessian matrix expressions of the objective function are derived. This also improves the optimisation efficiency compared with using the finite difference methods to solve gradient and Hessian matrix. To demonstrate the effectiveness of this proposed method, a conformal conical array with 454 elements has been designed. The amplitude and phase excitations were optimised by using the proposed method.
Keywords :
Hessian matrices; antenna arrays; antenna radiation patterns; conformal antennas; conical antennas; electromagnetic wave polarisation; gradient methods; optimisation; 3D conformal conical array; 3D copolarisation; DRR; Hessian matrix expression; amplitude excitation; cross-polarisation radiation pattern; current distribution; dynamic range ratio constraint; equivalence theorem; full-polarisation three-dimensional pattern synthesis; gradient matrix expression; optimisation procedure; phase excitation; three-dimensional conformal antenna conical array; trust region method;
Journal_Title :
Microwaves, Antennas Propagation, IET
DOI :
10.1049/iet-map.2015.0273