| Recently,wireless communication technology has been developed rapidly,which has put forward new requirements for the performance of wireless communication systems.Smart antenna technology has been widely used in the field of wireless communication to meet the high-capacity and high-speed communication requirements of the new generation wireless communication system,because of its advantages of anti-interference,anti-fading,capacity increase and consumption reduction.Beam-switching antenna is a typical kind of smart antenna and has good performance in engineering practice,with the advantages of low delay,low cost,high efficiency and high performance.With the advent of 5G era,beam-switching antennas are going to be used and developed more widely.In this paper,a variety of beam switching antennas were studied and designed.The effectiveness of the antennas were verified by comparing the measured results with the simulation results.On the basis of that,a beam-switching smart antenna system was combined with the three-beam switching antenna designed and the intelligent module.After a series of tests,it has been proved that the smart antenna system can improve the radio wave coverage of the environment and the communication quality.It provides a new choice for the antenna design of the next generation mobile communication system.The main work and innovations of this paper are as follows:1)A kind of three-beam switching antenna was studied and designed with a microstrip patch antenna and two quasi-yagi antennas.And this antenna can achieve beam radiation in the three directions of-90 degrees,0 degrees and+90 degrees,and the lobe width is above 60 degrees.Under the control of intelligent module,it can be used for beam tracking,realizing one-dimensional beam switching,and always pointing the beam to the user's area.Based on the simulation results,the antenna was processed,and the effectiveness of the antenna was verified by comparing the simulation results with the test results.2)Two four-beam switching antennas have been also realized on the basis of studying the influence of different structural parameters on the radiation characteristics of SIW.The first antenna can radiate in four directions of-60,-20,+20 and+60 degrees by being fed from different ports,and the lobe width can reach more than 40 degrees.The antenna has good practicability by comparing the test results with the simulation results.On the basis of the first structure,the second antenna used PIN switching diode to change the slot period of leaky-wave antenna,and realized the design of four-beam switching antenna electrically controlled.It has four same beam directions and lobe width with the first antenna,but the structure is more miniaturized and integrated.3)A series of tests were carried out to prove the actual communication performance of the beam-switching smart antenna system.The designed three-beam switching antenna was used as radiation unit to construct an automatic beam switching smart antenna system combined with the intelligent model.In the long straight hallway,the received power distribution and error vector magnitude distribution were tested in the case of the antenna radiation.Through analysis of the result,it has been proved that the beam switching antenna in this paper can ensure the steady coverage of radio waves,reduce the error rate and improve the communication quality of the system. |
PDF Full Text Request