Research On Miniaturized Wide-beam Electromagnetic Dipole Antenna

With the rise of the new generation of mobile communication technology(5G),more and more integrated terminal devices have requirements for miniaturization and wide beam coverage for antenna devices.The wide-beam antenna can be widely used in some complex electromagnetic environments to improve the reliability and safety of the communication system.At present,most wide-beam antennas have disadvantages such as complex structure and bulky size.Therefore,the study of miniaturized wide-beam antennas is of great significance to handheld terminals,base stations,satellite navigation and other equipment.Based on the classical electromagnetic dipole complementary theory,this paper mainly designs two miniaturized wide-beam electromagnetic dipole antennas.The main work of this paper is as follows:(1)An ultra-low profile end-fire wide-beam electromagnetic dipole antenna is designed.This antenna uses an arc-shaped cross metal patch as a vertical magnetic dipole,and an orthogonal short-circuit metal patch at the center as a horizontal electric dipole.By combining this pair of orthogonal dipoles and properly adjusting their phases,the antenna can obtain a cardioid radiation pattern with a wide beam performance with high front-to-back ratio.After optimization,this antenna has an ultra-low profile of 0.01?₀.The antenna works in the 4.9GHz frequency band.The measured performance shows that its impedance bandwidth is 4.1%(4.8-5GHz),the peak gain is2.11 d Bi,and it has a stable wide beam radiation pattern on both the E and H planes,and the half-power beam widths are respectively 128°and 176°.(2)On this basis,in order to realize the beam scanning of antenna pattern,this paper designs a pattern reconfigurable antenna.Since the direction of the equivalent electric dipole is determined by the number and location of the short-circuit pins connected to the circuit,the on-off of the short-circuit pins is controlled by loading four diodes on the top of the antenna substrate as RF switches,so as to adjust the direction of the equivalent electric dipole and change the maximum radiation direction of the antenna.The improved antenna can achieve nine operating modes of the antenna and 360°beam scanning on the horizontal plane.(3)A wide-beam electromagnetic dipole antenna with all-ground normal radiation is designed.This antenna combines a dipole and a split loop antenna and places it on a metal floor,thereby realizing a wide-beam normal radiation antenna with a simple structure.The antenna works in the5.8GHz ISM frequency band,the impedance bandwidth obtained by the test is 21.1%(5.16-6.38GHz),and the peak gain is 3.95d Bi.The actual measured half-power beam widths on the E and H planes are 129.9°and 110.2°,respectively.