Design Of Low RCS Microstrip Antenna Using Artificial Magnetic Conductors And Defected Ground Structure

Stealth technology is an important means to improve penetration capability and security performance of combat platforms such as missiles,warplanes and warships in high-tech integrated electronic warfare.For low visibility platform,antenna is one of the main contributors to its total radar cross section.Therefore,it is increasingly important to consider the radar cross section of antenna.Microstrip antenna is small in size,light in weight,low in profile and easy to conform to the surface of aircraft.It is often used as low scattering antenna of rocket or missile and has been widely used in military field.Combining with the research hotspots and progress of stealth technology of microstrip antenna,and aiming at the limitations or shortcomings of the published research,the design of microstrip antenna with low radar cross section and high performance is deeply studied through theoretical analysis and simulation measurement.The main work and innovations are summarized as follows:1.Through etching defected ground structure on the ground of the artificial magnetic conductor unit cell and moving its reflection phase curve to low frequency without changing the size of the patch on the surface of the structure,the reflection phase difference of 180°±37°can be obtained in the lower frequency band.Applying this artificial magnetic conductor to the microstrip antenna,the radar cross section reduction is achieved in the lower frequency band,which also provides a new idea for miniaturization design.2.The basic theory of antenna scattering is analyzed,and a microstrip antenna based on artificial magnetic conductor and defected ground structure is proposed.The simulation results show that the radar cross section of the antenna decreases significantly in a wide frequency band while the gain of the antenna increases significantly.The measured results are in good agreement with the simulation results.3.Applying above design method to the low radar cross section design of microstrip antenna array.The radiation and scattering characteristics of the array antenna are simulated.The results show that the antenna array can basically remain the antenna radiation performance unchanged and achieve good radar cross section reduction effect simultaneously.