Using Fdtd Application In The Calculation Of The Antenna And A New Type Of Antenna Array Design

CHIPIC is an electromagnetic particle-in-cell code which is developed by our country and our country possesses the intellectual property of CHIPIC. The implementation of CHIPIC is based on Finite-Difference Time-Domain (FDTD) and PIC algorithm. In this paper, the designs of algorithm of CHIPIC antenna module and a new quasi-yagi antenna array are presented and analyzed.Firstly, the FDTD method is reviewed, including difference format, the stability condition, the PML absorbing boundary condition and the exciting source. Then the paper improved nonuniform grid method by PADE algorithm.Secondly, antenna module is a sub-module of CHIPIC, which is used for solving radiation pattern of an antenna by Huygens near-to-far-field transformation. According to the characteristics of CHIPIC and FDTD near-to-far-field transformation algorithm, the kind of antenna algorithm is designed. The horn antenna experiment result and the theoretic result show that these results agree with calculated values.Yagi antenna is studied systematically. The characteristic and application of the microstrip balun structure are also described in detail especially in half-wave antenna . Based on the common balun, a new balun are designed. The structure of the new balun is simple and the relation between dimension and wavelength is not very important, so the bandwidth is broad.The new balun structure is used to design a new micro-strip quasi-yagi antenna from 16GHz to 24GHz, the relative bandwidth is 37%, absolute bandwidth is 7GHz. The antenna gain is 5dB. The antenna array is composed of balun antenna element and T-junction power divider for enhancing the antenna gain, and the gain increased to 9dB. So, the new antenna has the characteristic include yagi antenna and micro-strip antenna, and its bandwidth is broad.