Multi-beam Focusing Lens Antenna

Imaging technologies using millimeter wave offer unique measurement means in plasma diagnostics. A focal plane imaging is limited in catching object when spot-focusing horn lens antenna is applied in ballistic wake microwave interferometer. So we consider to designing multiple beam focusing horn lens antenna in order to augment the range of catching and enhance the probability of hitting the target. Multiple beam focusing horn lens antenna is an important part of interferometer. Multiple beam lens antenna's designing and measurement are crux because antenna's far-field focusing ability is used to judge interferometer's capability. Focusing lens antenna's critical specifications are the position of the maximal electric field value and space resolution. Single beam focusing lens antenna is the basis and crux of the multiple beam focusing horn lens antenna. Only adequately and accurately analyzing focal area's position and resolution, consider the influence when horn feed's position is displaced to different location, we can design multiple beam focusing horn lens antenna. We designed, simulated and experimented multi-beam lens antenna based on spot-focusing lens antenna's designing, computer simulation, experiment and analysis.In this paper, the author adopted different methods to discuss resolution including geometry optics, Gaussian beam and vector diffraction integration. We used ray tracing to analyze focal area's position and made further analysis of the affection with horn position's change. Through analyzing and experimenting, we discussed beam feeding network and multiple beam's coupling. We analyzed the affection on resolution induced by horns intervals'change, furthermore, we proved this affection by experiment. At last, we discussed the spillover and illumination level. With experiments of single beam and multiple beam lens antenna, we got results that their specifications achieved the project goals. The system will be utilized to date present spot-focusing lens antenna. With further improvement of this system, it is possible to have more completed and efficient sampling of focal plane.