Design And Analysis Of Broadband Omnidirectional Antenna Used For Mobile Communication

With the continuous development of mobile communication technology,a variety of communication equipments continues to increase,people's demand for the antenna is also increasing.In order to reduce the complexity of the entire communication system,reduce the size and weight of the communication equipments and improve the portability of the equipments,it is often necessary for an antenna to satisfy the work of multiple communication devices at the same time,which requires the antenna to have a relatively wide operating bandwidth to cover each working band of the communication equipment.In addition to bandwidth requirements,in some communication systems,the antenna also needs a low profile,miniaturization and other characteristics to meet the requirements of the installation environment.On the market for broadband,low profile,high current gain,the whole demand-directional antenna,this paper mainly completed the following work:(1)low-profile design of a broadband vertically polarized omnidirectional antenna,which in the 1710 MHz-2690 MHz VSWR less than 2.0 in the frequency band,gain is larger than 4 d B,roundness less than 1 d B,the polarization size of less than 20 mm;(2)a wideband low-profile design of horizontally polarized omnidirectional antenna,the antenna in the 1710 MHz-2690 MHz frequency band VSWR less than 2.0,greater than 1 d B gain,roundness less than 3 d B,the antenna longitudinal size of less than 2 mm;(3)design a wideband low-profile dual-polarized omni-directional antenna,the antenna in the 1710 MHz-2690 MHz frequency band,horizontal polarization and vertical polarization port VSW R less than 2.0,4 d B gain is greater than the vertical polarization,horizontal polarization gain is greater than 2 d B,vertically and horizontally polarized roundness less than 3 d B,two-port isolation greater than 30 d B,the entire longitudinal dimension of the antenna is smaller than 80 mm;(4)design of a broadband high gain omni-directional dual-polarized antenna,the antenna in the 1710 MHz-2690 MHz frequency band,horizontal polarization and vertical polarization port VSWR less than 2.0,8 d B gain is greater than the vertical polarization,Horizontally polarized gain greater than 7 d B,vertically and horizontally polarized roundness less than 3 d B,two-port isolation greater than 30 d B.The antenna is modeled,simulated and optimized by CST Microwave Studio? electromagnetic simulation software.The results of this test show that the experimental results of the above antennas are in good agreement with the simulation results.Meet the requirements of indicators.In addition,this paper also carries on the theoretical analysis to the designed antenna,has described the working principle and the design method of the antenna in detail.The antenna designed in this paper has the characteristics of broadband,low profile,high gain and omnidirectional,and it can be widely used in mobile communication equipments.