Research On The Missile-borne Ultra Wideband Miniaturized Antenna Array

The missile-borne ultra-wideband?UWB?antenna arrays are researched in this thesis.The main content of this thesis can be summarized as follows:Firstly,the related concepts involved in this thesis are explained,the research status and existing problems are discussed,the background and significance of the topicof the missile-borne UWB miniaturized antenna are expounded,the basic theories and methods of this thesis are introduced.Secondly,the research on the missile-borne UWB miniaturized antenna array is carried out.The author's major contributions are outlined as follows:1.Research on the missile-borne UWB miniaturized TEM horn antenna arrayThe first part of the dissertation is the research on the missile-borne UWB miniaturized TEM horn antenna array.The research work include the following two sections:.?1?Study on the UWB miniaturized semi-structured TEM horn antennaIn order to meet the UWB and miniaturization requirements of the missile system for the antenna,the semi-structured TEM horn antenna is selected as the array element for the designing of the missile-borne antenna array.In the design of the antenna element,the miniaturization and the impedance matching at the low frequency of the antenna are improved by the loadings of the low-frequency conpensation and the matching strip,the low-profile property of the antenna is realized by using semi-structure according to the mirror image principle.The designed TEM horn antenna has a minimum operating frequency of1.7 GHz for Voltage Standing Wave Ratio?VSWR??2.0,a forward gain?at?=90°,?=0°?of greater than-1.8 dBi over the band of 2.0-20.0 GHz,and a size of only55.0mm×35.0mm×28.0mm?except for the ground plate?.The antenna element is fabricated and measured.The measurement results verified the feasibility of the antenna as an element in the integrated simulation of the missile and the antenna array.?2?Design of the missile-borne UWB miniaturized TEM horn antenna arrayIn the integrated simulation of the missile and the antenna array,the right-angle groove for antenna on the bomb is optimized to be wedge-shaped to reduce the impact of the missile platform on the antenna.The simulation results reveal that the designed antenna array can achieve the VSWR?2.0 and the forward gain over-0.5 dBi within the band of 2.0-20.0GHz,which meets the application requirements of the system.2.Design of the missile-borne UWB miniaturized Vivaldi DF antenna arrayThe second part of the dissertation is the design of the missile-borne UWB miniaturized TEM horn antenna array.The research work include the following two sections:.?1?Study on the UWB miniaturized Vivaldi antennaAccording to the requirements of UWB and miniaturization,Vivaldi antenna is selected to be the element for the missile-born direction-finding?DF?antenna array.In the design of the antenna element,the absorbing resistors are loaded at the end of the antenna to reduce size of the antenna,and two such antennas are placed cross with additional 90°phase difference to achieve circular polarization.The simulation results show that the antenna with the size of?0.36?₀×0.33?₀ can achieve the VSWR?2.4 within the frequency band f₀-4f₀??₀ is the free-space wavelength at frequency f₀?,and the right-hand circular polarization?RHCP?gain is above-5.3 dBic within the±65°beam in the E-plane and H-plane,which indicate the antenna can serve as the element in the integrated simulation of the missile and the antenna array.?2?Design of the missile-borne UWB miniaturized Vivaldi antenna arrayIn the integrated simulation design of the missile and the antenna array,the mutual coupling between the antennas is reduced by adding metal plates between the elements.The simulation results show that the five antenna elements can achieve the VSWR?2.4 and the RHCP gain is above-6.9 dBic in the target beam range within the frequency band of f₀-4f₀.All these results satisfied the design requirements.Finally,the work of this thesis is summarized,and the problems that need further research are pointed out.