Research On Antenna Array For High Resolution Passive Millimeter-wave Imaging

The multi-beam antenna is an important part of the project"Research on Theory and Technology for High Resolution Passive Millimeter-wave Imaging", which supported by The Nature Science Foundation of China.Conventional Passive Millimeter-wave Focal Plane Array(FPA) needs small feeds for gaining dense and uniformitarian beam.The beam width inverse proportional to the structure of the feed, therefore there would exist overlap between the beams of adjacent feeds,which shall deteriorate the quality of imaging. However,interferometric measurements for the overlap between the beams of adjacent feeds can generate more image pixels than the conventional focal plane imaging. Combining coherent technology with incoherent technology have been researched by some academicians. Under this background,this dissertation introduce a new design focal plane array method combining coherent technology in order to further enhance the resolution.This dissertation first represent state-of-the-art of multi-beam antenna. Then influences of lateral offset-focus on the antenna beam are presented. After that,by analysing correlation between the beams of adjacent feeds in passive millimeter-wave PFA,a method is proposed to confirming the distance between feeds, which applys for the interferometric measurement technique. Through experiment we can show the method is more effective than the conventional FPA imaging methods ever did and offer theoretical support for this technology. At last,this dissertation designs a focal plane array which including ,selection reflecting antenna and the structure parameters of the feeds, optimization of the array style.