X-band Planar Wave Antenna Based On Substrate Integrated Waveguide

Antenna is one of the most important devices in the co mmunication system.With the progress of science technology,it plays an more and more important role in many different fields.With it's rapidly development,people now have higher requirements of it.Traditional horn antenna has the advantage of being more directive,but its large size makes it difficult to be integrated,which greatly limited the horn's development in modern application.Substrate integrated waveguide combines the characteristics of first-generation waveguide on the quality and the second-generation waveguide on its volume size,so it is more applicable to various microwave devices.The horn antenna based on SIW follows the growing trend of miniaturization and integration.However,the smaller antenna's volume is,the smaller its aperture surface is,which may lead to the defects such as the phase distribution may be formed unevenly,the radiation performance is weakened,and the front-to-rear ratio is reduced.By using a uniform dielectric lens as the adjustment of the front-end phase could increase the radio performance of the horn antenna.This way the problem could be solved to a certain extent.However,here also comes a new question---most of the lenses are loaded outside the apertures,when the size of antennas gets bigger,a more complex difficulty arises for us to work it out.Based on the above disadvantages,this passage uses a phase superposition technology of electromagnetic wave to design the X-band(8-12 GHz)SIW plane wave antenna,which could reduce the volume of antenna,increase the radiation distance and also reduce the RCS of antenna.Besides,adding metal baffles which follows the law of decreasing distribution on the basis of SIW horn antenna could increase the performance of the antenna without increasing its volume.As for the plane wave radiates,since the attenuation of plane wave in free space is less than that of the spherical wave,so the radiation distance could be extended.The experiment result shows that the phase of the radiated wavefront of the antenna is significantly improved in the range of 80 degrees directly ahead of the contact point between the horn and the feed,and the spherical wavefront is approximately converted into a plane wavefront by the phase adjustment of the metal baffle.In the meanwhile,the HPBW of plane E and plane H is obviously narrowed,that is,the width of plane H is 20.4 degrees,and the width of plane E is 44 degrees.So we can draw to the conclusion that---the radiation energy is concentrated then,and the orientation is greatly improved which make it could achieve the long-distance transmission.At the same time,the adhering on the metal baffles of absorbing material has not only reduced the dielectric loss and magnetic loss but also reduced the RCS of antenna,which could effectively preventing the electromagnetic interference and the detection of equipment from the outside world.