Research On Novel Multi-band Antenna With Large Frequency Ratio

With the emergence of various millimeter-wave applications,muti-band antennas that can only operate in the traditional microwave band will be difficult to meet the requirements of future high-speed microwave and millimeter-wave wireless communications.Therefore,the design of a multi-band antenna with large frequency ratio which can work in both microwave and millimeter-wave bands has very important practical application value for future communication applications.Based on the characteristict that the substrate integrated waveguide structure(SIW)can be equivalent to a metallic strip in the microwave band much lower than its cut-off frequency,three novel multi-band antennas with large frequency ratio are designed in this paper.The main contents and innovations of this paper are as follows:1.A novel dual-band antenna with large frequency ratio is designed for WiFi and 5G communication.Without increasing the volume of the original single antenna structure,the proposed antenna integrates the SIW slot array operating in millimeter-wave band into the loop antenna operating in microwave band.The SIW slot array working in millimeter-wave band and the loop antenna working in microwave band share one antenna radiation aperture.The designed antenna only occupies a space of 18.5×10 mm2,and has the characteristics of simple structure,high integration and flexible frequency ratio adjustment.2.A novel hepta-band antenna with large frequency ratio is designed for WLAN,LTE and 5G communication.In millimeter-wave band,in order to enhance antenna directivity and improve impedance bandwidth,a series of parasitic electric dipole elements are introduced to couple with slot arrays based on the structure of SIW slot arrays.In the microwave band,the proposed antenna regards SIW slot arrays as its main radiation structure.The designed antenna only occupies a space of 18×54.5 mm2,and has the characteristics of simple structure,high integration,high frequency ratio and high isolation.3.A tri-band MIMO antenna with large frequency ratio is designed for 5G communication and ultra-high speed near-long distance communication based on Q-Linkpan standard.In this design,the high frequency MIMO antenna working in millimeter wave band and low frequency MIMO antenna working in microwave band are integrated,which achieves the performance characteristics that can operate in both microwave band and millimeter-wave band without increasing the size of the original single MIMO system.Meanwhile,the feeding ports of high-and low-frequency signals in MIMO antenna elements and the feeding ports of each MIMO antenna elemnet have high isolation characteristics,and the correlation coefficient among MIMO channels satisfys the corresponding design criteria(ECC<0.5).