Research On Millimeter-Wave Microstrip MIMO Antenna Based On Fifth Generation Mobile Communication

With the popularization of 4G network technology,it brings convenience to people's life and makes the world more colorful.The research of the fifth generation mobile communication technology can make the wireless communication faster,more stable and more reliable.Multi-input and multi-output technology(MIMO)can achieve significant diversity gain,and effectively increase channel capacity and communication reliability on the basis of no increasing transmitting power.Low frequency spectrum resource is strained,so that 5G mobile communication frequency band will move toward high frequency.Millimeter wave with its rich spectrum resources cause people's attention.Therefore,the design work on millimeter-band MIMO antennas is of great significance to promote the development of 5G.Meanwhile,5G Mobile communication has backward-compatible characteristics.To save resources,it is also necessary to design the microstrip MIMO antenna in the low frequency band of 5G.Based on the relevant information of the fifth generation mobile communication,a few microstrip MIMO antennas are designed based on the 5G communication-related frequency bands.The content of this dissertation are as follows:1.Two microstrip MIMO antennas based on the fifth generation mobile communication are proposed.The antenna radiation unit is arranged in a ring form.A two ports MIMO antenna array is designed by placing the two radiation units in parallel.In order to increase the isolation between the radiating units,opening the rectangular groove on the ground,increasing the protrusion structure and increasing the L-shaped groove are done.The antenna is actually made and tested,the isolation degree is lower than the-15 db in the band of 3.3-5.59 GHz.Based on the two ports MIMO antenna,a four-ports MIMO antenna array is designed.To realize the increasing of the isolation between ports,the isolation network is implied on the middle of the ground.Optimize the antenna size,make the antenna and test,isolation is lower than the-15 db in the band of 3.09-3.75 GHz and 4.25-5.32 GHz,of which band widths are 660 MHz and 1.007 GHz respectively.2.Two millimeter-wave microstrip feed slot MIMO antenna array based on fifth generation mobile communication is proposed.The antenna is in the form of a microstrip feeder slot antenna,a microstrip feed wire is located on one side of the substrate,and a slotted floor is on the other side.Based on the microstrip feeder slot antenna unit,we designed two kinds of four ports MIMO antenna arrays,which are the horizontal four ports MIMO antenna array and the vertical four ports MIMO antenna array.The S parameters,the surface current distribution,the radiant patterns and the gain are simulated by HFSS for each four ports MIMO antenna array.The operating bandwidth of the antenna is from 34.5GHz to 40 GHz,the port isolation is under-20 dB for the vertical four ports MIMO antenna array and the horizontal four ports MIMO array.Meanwhile the isolation of the vertical four ports MIMO antenna array is better.Calculation results shows that all these two antennas meet the requirements of modern handheld mobile terminals.The miniaturization of the antenna is an inevitable trend to meet the needs of mobile terminals in the future.Maintaining the excellent performance of the antenna while allowing the structure to be more compact requires further consideration and research.