Research And Design Of New Antenna Based On Liquid Crystal Composite

Liquid crystal materials are widely used in high-frequency planar antenna structure because of its electrically controlled adjustable dielectric constant and low high-frequency dielectric loss.As a dielectric plate,liquid crystal planar antenna can realize continuously adjustable electronic control of different parameters,such as frequency,direction pattern,etc.In addition,it is used to realize the miniaturization and low profile of the antenna.In this paper,the microstrip antenna on liquid crystal substrate is studied to realize the constant frequency wide angle scanning of frequency controlled harmonic beam,and the method to improve the radiation gain is studied.The research content of this paper is divided into the following four aspects:1.This paper introduces the research background,development course and research significance of liquid crystal antenna,the radiation principle of microstrip antenna and the beam scanning principle of leaky wave antenna,the liquid crystal polymer material,the method to improve the change range of liquid crystal dielectric constant,the principle of liquid crystal electric control,and finally the physical production method and production process of liquid crystal antenna.2.A leaky wave antenna using a new liquid crystal material as a dielectric plate is designed.This kind of material can change the physical properties of dielectric constant in a large range and make the phase constant change greatly.Finally,wide angle scanning is realized: the scanning angle of single terminal radiation is-56 ° — 58 °;the scanning angle of double terminal radiation is-70 ° —-112 ° and 60 ° — 110 °.3.A leaky wave antenna with double row slot liquid crystal is designed.Using the electromagnetic field superposition principle of double row slot array,the maximum radiation gain is increased by 8.92 d B.Since the phase constant is not changed,the scanning angle is kept unchanged.4.At last,the paper summarizes the content of the whole paper,looks forward to the future research and development potential of liquid crystal antenna,and explores the future research direction.