Research On Scanning Characteristics Of Wideband Dual-polarized Array Antenna

With the rapid development of electronic information technology and the explosive growth of communication channel capacity,wideband dual-polarized array antenna has gradually become the mainstream of antenna design because of its ability to cover more communication bands,excellent ability to combat multipath fading and high design freedom.With the continuous evolution of wireless communication systems towards high-speed,wide coverage,multi-functionality,in addition to the basic wideband and low polarization sensitivity,the system usually also has additional requirements for the radiation and scanning characteristics of the designed array.In the case of dual-polarized arrays,for better performance,systems often expect the scanning gain of the arrays to be consistent at different polarization,but this has received little attention.Based on the above problems,this paper aims at the gain consistency between different pola rizations of the broadband dual-polarized array over a large scanning range.The sparae array and uniform array are designed with the magneto-electric dipole which has nearly identical E-and H-plane patterns.The main research results of the paper are sum marized as follows:1.This paper puts forward a specific quantitative index to assess the consistency of the E-and H-plane patterns of the unit and analyzes the effect of this performance on the scanning characteristics of the dual-polarized array.The analysis includes theoretical aspect and simulation aspect.The results show that the performance of the unit can significantly reduce the scanning gain difference between different polarizations of dual-polarized array antenna.2.A miniaturized magneto-electric dipole sparae array unit is designed,and the sparse array synthesis of linear array and planar array is carried out.The designed sparse linear array achieves 47.6% bandwidth(4-6.5GHz)while scanning up to ±60 without grating lobes,and the gain difference between different polarizations of the antenna is less than 2dB in the scanning range.Besides,The designed sparse linear array achieves60.87% bandwidth(4-7.5GHz)while scanning up to ±45,and the gain difference between different polarizations of the antenna is less than 1dB in the scanning range;The designed sparse planar array achieves 72% bandwidth(4-8.5GHz)while scanning up to±60 without grating lobes,and the gain difference between different polarizations of the antenna is less than 2dB in the scanning range.3.A magneto-electric dipole uniform planar array unit and a linear array unit are designed,and the array models are established to analysis their scanning performance.The designed 12×12 planar array achieves 50% bandwidth(4.5-7.5GHz)while scanning up to ±60 without grating lobes,and the gain difference between different polarizations of the antenna is less than 0.5dB in the scanning range.Besides,the designed planar array achieves 56% bandwidth(4.5-8GHz)while scanning up to ±45,and the gain difference between different polarizations of the antenna is also less than 0.5dB in the scanning range,except for the edge frequency points(8GHz);The designed 12-element linear array achieves 40% bandwidth(5-7.5GHz)while scanning up to ±45 without grating lobes,and the gain difference between different polarizations of the antenna is less than 2dB in the scanning range.