A Study On Millimeter-Wave High Gain Dielectric Lens Antennas Fed By Phased Arrays

With the rapid development of 5G communication,satellite positioning,radar detection,electronic information confrontation and ship tracking,the demand for millimeter-wave band antennas is more and more extensive,whose requirements for the technical specifications are also getting higher and higher.Phased array fed dielectric lens antennas present broad application and research prospects in the millimeter-wave band.These antennas often have the features of wide scanning angles,high gains,low profiles and low cost.This thesis studies the technology of phased array fed dielectric lens antennas.The main contents of this thesis include:Firstly,the research background and application scenario of millimeter-wave dielectric lens antennas are introduced.At the same time,the development status of dielectric lens antennas at home and abroad is summarized.Secondly,the basic working principle of traditional Luneberg lens antennas is reviewed,and the geometrical optics method is used to analyze Luneberg lens antennas.Transformation optics is used to compress the profile of traditional Luneberg lens antennas.In addition,the effective medium theory is applied to realize the required effective permittivity with drilling holes distributed in solid dielectric materials.Thirdly,a new form of wide-angle scanning phased array fed ellipsoid dielectric lens antenna in Ka-band is designed.It is fed with a 1×9 microstrip patch phased array.The lens antenna is able to scan up to ±45 ° along the phased array direction.By taking advantage of transformation optics to design the ellipsoid dielectric lens antenna,the antenna profile is reduced,and the issue about the combination of the phased array and dielectric lens is solved by the element pattern superposition principle.The experimental results show that the designed lens antenna has good antenna characteristics.Fourthly,a phased array fed biconvex dielectric lens antenna in Ka-band is designed.It is fed with an 8×8 microstrip patch array.The dielectric lens antenna is able to scan up to ±30 ° in two dimensions.Throughout applying the phase conjugate techniques,the desired excitation amplitude and phase distributions can be acquired for the accurate beam scanning performance.Finally,a new form of multi-beam cutted spherical lens antenna in S-band is designed.The beam is switched with 18 microstrip patch antennas.On the vertical plane,the beam is down-tilted about 18° and the beamwidth is 29.3°.On the horizontal plane,there is a 360° beam coverage and the beamwidth is 23.5°.Simulation results show that the antenna can be used to realize the oblique beam on the vertical plane and the beam coverage on the horizontal plane,which is suitable for multi-beam communication systems.