Design And Anufacture Of Small CW Irradiation Antenna

With the development of electronic technology,various semiconductor components have been widely used in electronic systems and electrical systems and weapon systems.Since semiconductor devices and integrated circuits are very sensitive to electromagnetic pulses,which may cause electronic devices to suffer serious damage.In order to ensure the normal operation of weapons and equipment in the electromagnetic pulse environment,GJB 8848-2016 has been implemented since August 1,2016,and for the electromagnetic pulse effect of the system continuous wave(CW)irradiation methods are given to predict the electromagnetic pulse effect of the system.The radiation antenna covering the 100kHz~500MHz frequency range and being able to illuminate the whole system is particularly critical.In order to carry out CW irradiation test method research,this article refers to a variety of CW irradiation test antenna that have been developed abroad and select the elliptical radiation antenna as a CW radiation antenna.For the performance research,a small radiation antenna with a radius of 1.5m was designed to investigate the influence of the structural parameters of the elliptical radiation antenna on its performance.The simulation results show that the antenna can radiate the plane wave in the near field in the 100kHz~500MHz.On this basis,the antenna loading mode is designed.The winding resistance magnetic ring is set on the vibrator to complete loading,and a simple fixture is set up to test the magnetic ring impedance.By testing different magnetic rings and different ways of winding resistance,the final selection is sample 3,and four resistors of 40 ohm are wrapped on the magnetic ring.The antenna feed mode is designed to feed the large size irradiated antenna.According to the input impedance of the antenna,the 1:9 transfer line balun is designed and produced.The insertion loss,the reflection loss and the balance to imbalance are all satisfied in the 100kHz~100MHz by testing.In order to prevent the influence on the antenna radiation field,the antenna bracket is made of FRP.According to the antenna feeding mode,the antenna oscillator is made with the coaxial line,and the calculated load resistance and the measured magnetic ring resistance are obtained.The magnetic ring is placed on the antenna at equal intervals.After completing the antenna,the VSWR and radiation field are tested.The results show that the antenna' VSWR is less than 7 in the 100kHz~100MHz,the main direction of the electric field is horizontal in the 10MHz~100MHz,the main direction of the magnetic field is in the horizontal direction in the 100kHz~100MHz and perpendicular to the main direction of the electric field.The impedance of the antenna radiation field in the 2MHz~30MHz is close to 377?.The test results show that the antenna can radiat plane wave above 10 MHz in the near field.