Research On Several Key Technologies Of Electromagnetic Target Simulator In Hardware-in-the-loop Simulation System

Hardware-in-the-loop simulation is a low-risk,high-efficiency and high-reward technology for the development of seekers.The technology can substitute shooting tests,shorten the development cycles,increase efficiency,reduce costs and obtain operational data in real time.The electromagnetic target simulation subsystem in the hardware-in-the-loop simulation system,or called the electromagnetic target simulator,uses antenna array,compact range or millimeter wave/infrared compound technology to simulate the target movement.With the rapid and diversified development of military equipment manufacturing in our country,the target simulation systems need to be upgraded.These upgrades include the bandwidth upgrade of wideband antenna element for the centimeter/millimeter wave compound target simulator array and the millimeter wave simulation accuracy upgrade for the millimeter wave/infrared compound target simulator.These upgrades are of great significance to China's contemporary national defense construction.In this paper,several key technologies of the electromagnetic target simulator are studied,including the broadband antenna element design of the centimeter/millimeter wave compound target simulator array and solution for the contradiction between the infrared transmittance and the millimeter wave quiet zone quality of the millimeter wave/infrared compound target simulator.These two technical problems are of the combination of centimeter wave and millimeter wave,millimeter wave and infrared wave in the electromagnetic target simulation systems.Firstly,a novel dual-band dual-polarized compound Vivaldi antenna(DBDPVA)with 2-40 GHz bandwidth coverage is proposed and implemented to solve the technical problems of the antenna element design in the centimeter-wave/millimeter-wave compound array.The design combines 8-40 GHz and 2-8 GHz double-slot line Vivaldi antennas into a dual-band Vivaldi antenna by nesting method,which solves the problem of the combination of centimeter wave and millimeter wave antennas in one aperture.By adopting the double-slot radiation structure and the adjustment of the feeding network structure,the structural difficulties at the slotline feeding point of the Ka band orthogonal polarized Vivaldi antenna are solved.The measured-10 dB impedance bandwidth of the DBDPVA covers 2-8 GHz and 8-40 GHz;the vertical and horizontal units have similar radiation characteristics;the maximum gain is higher than 4.6 dBi at 2-40 GHz;and the maximum gain is near 10 dBi at 6-40 GHz.The measured results show that the bandwidth,polarization mode,gain and 3 dB beam width of the DBDPVA can meet the technical requirements of the centimeter /millimeter wave compound target simulation array.Secondly,in order to solve the contradiction between the infrared transmittance and the millimeter wave quite zone quality in the millimeter wave/infrared compound target simulation system,a compact range reflector antenna with graphene infrared window is proposed for the first time.The basic parameters of graphene in the design of infrared window are grasped by study the characteristics of graphene in both millimeter wave and infrared.According to these basic parameters,a novel millimeter wave/infrared compound compact range reflector antenna with graphene infrared window is designed.The graphene infrared window has an infrared transmittance reference value of about 90%.Full-wave simulation results show that the compound compact range reflector antenna has a circular quiet zone aperture with diameter of 140 mm based on the standard that the peak-to-peak value of amplitude unevenness in the quiet zone less than 2 dB at 35 GHz,and the peak-to-peak value of phase unevenness in the quiet zone is 0.66 degree.Compared with the compact range reflector antenna with conducting inductive meshes infrared window,this dissertation proposes that the compact range reflector antenna with graphene infrared window has excellent infrared transmittance and uniform millimeter wave quiet zone phase characteristics,which resolved the contradiction between the infrared transmittance and the millimeter wave quiet zone quality in the millimeter wave/infrared compound target simulation system.