| The study of Liquid-Metal antenna has been studied and three kinds of LM antenna are proposed in this paper.According to the current status of domestic and international liquid antenna designs,mainly focused on the design of liquid metal antennas and the application of liquid metal,a comparative summary of different types of liquid-metal-based antenna designs is presented,and the gallium indium tin alloy is found to be relatively stable in electric performances and suitable for large-scale manufacture,which could bring distinct advantages in the design of reconfigurable antennas and soft antennas.Based on the characteristics of the liquid metal gallium indium tin alloy,in-depth research on the design of reconfigurable antennas and liquid metal antennas was carried out.A frequency reconfigurable antenna and a reconfigurable antenna with tunable polarization between left-hand and right-hand are proposed.While used in the design of reconfigurable antennas,the liquid metal appears to be liquid at room temperature,which is alterable,and its basic structure is a theoretically lossless transmission structure.Compared with reconfigurable antennas using common microwave switches such as PIN diodes and MEMs,liquid mental antenna has a better performance in antenna efficiency.Because of its chemical characteristics,the gallium indium tin alloy will react chemically when coming into contact with traditional metals.Therefore,liquid metal and solid metal in an antenna should adopt a coupling structure,which would cause a harmful effect on efficiency of the antenna.What’s more,an in-depth study of soft antenna has been carried out,and the application directions and design methods of soft antenna are summarized.A broadband folding portable mono-pole antenna working at the relatively high frequency of ultra-short wave band is designed in this paper.The liquid metal is used to fill the flexible hollow dielectric material as the radiation structure of the antenna,in this way,the antenna can be bent and folded drastically and repeatedly.The main ideas of this paper are theoretically verified through the design of the following three antennas.1.A frequency reconfigurable antenna using the fluid characteristic of liquid metal.The radiation patch of this antenna is made of liquid metal and can be deformed.By changing the size of the radiation patch,the resonant frequency of this antenna will change.The antenna can work at two different frequency,and performs well at the center frequencies of those two working modes.2.A polarization reconfigurable antenna using the fluid characteristic of liquid metal.On the basis of coupling microstrip transition structure,a feeding network is designed.It can change the output phases of the network by changing the position of liquid metal.And a polarization reconfigurable antenna is realized by using this feeding network.At the center frequency,this antenna has a good radiation pattern.3.A soft and folding antenna using liquid metal as the material of radiation structure.This kind of soft antenna can break traditional metal materials’ limit of degree of deformation and greatly improve the deformation ability of soft antenna. |
