Research Of Slotted Circularly Polarized Antenna And Array Based On SIW

SIW is one of the significant waveguide structures in mm-wave due to the advantages of low-profile,easy to integrate and low loss.Circularly polarized(CP)antenna is widely used in navigation system,communication system and radar system due to the advantages of antiFaraday effect and multipath effect.Navigation system and radar system need wide beam CP antenna.Communication system needs high-gain CP antenna.The article does research according to the two points.The study of this article is divided into the following parts:1.Slot etched on SIW often used for radiation.The article introduces SIW technology and the radiation characteristics of SIW slot,then,the polarized of electromagnetic has been introduced.2.A wide beam CP antenna based on SIW,which fed by coupling,is designed.The operation band of the antenna is X-band,which achieves the 3d B AR beamwidth of 150°on the plane of phi=0° and 200° on the phi=90°.The chapter also do the study of near-field coupled feeding,which is important in the study of magneto-electric dipole antenna.3.The article design a 90°SIW electric bridge(EB)that works in X-band with 20%operating band.A CP antenna is designed by connecting the EB and transverse slot antenna.The antenna achieves the gain of 6d Bi,and two elements array based on the antenna,which achieves 8.6d Bi,is designed.4.The antenna introduced above has a large size,so it is not suitable for multi-element array antenna design.The article proposes the improvement measures.Firstly,titled slot replaces the transverse slot,then,the layered design of SIW EB and radiation element,more then,two radiation elements fed by one SIW EB.The antenna size is reduced to a suitable size.Then,a 4*4 high gain dual-CP array is realized.The antenna array achieves a high gain of 17±0.2d Bi,a normalized sidelobe level(SLL)of less than-10 d B,and a front-to-back ratio of less then-30 d B.