Research On W Band FMCW Foregin Body Detection Radar

The main research of this dissertation is the radar front-end module and the antenna part of an airport runway foreign matter detection radar. System of the radar is heterodyne frequency modulated continuous wave. The transmission branch includs transmitting eight frequency multiplication module,and the receiving branch circuit comprises a low noise receiving module and a local oscillator eight frequency multiplication module. Millimeter wave antenna is a substrate integrated waveguide slot arrayantenna.At first,in the introduction part, the research background and significance of the subject are introduced in detail, and the development history and development trend of the foreign body detection system in the airport runway are also analyzed.In this paper, the theoretical basis of the substrate integrated waveguide slot array antenna is derived from the traditional rectangular waveguideslot array antenna. So in the second chapter, this paper introduces the related theoretical knowledge of the design of the substrate integrated waveguide slot array antenna,based on this, the attempt of the two design methods is carried out.One is to change the length of the seam by a fixed offset. The other is to adjust the length of the gap by changing the offset, so as to make the excitation amplitude weighted, and finally realize the low sidelobe.In the end, The second scheme is selected,and according to the index, the design of radiation front, coupler and gap, feed network in the unequal power divider branch waveguide power divider, the short circuited end folding were completed. The overall simulation of the antenna array with the feed network achieves the design goal,then the antenna is processed. In the paper, the test method is introduced in detail and the test results are analyzed.The measured results basically meet the expectations, and provide guidance for the follow-up improvement and optimization. The development of front end module mainly includes eight frequency multiplication module and low noise receiving module. In the fourth chapter, the working principle of the super heterodyne frequency modulation continuous wave radar system is introduced in detail. According to the requirements, the link design is completed.The main work includes the link budget, the election of the chip, the design of passive circuit and so on. Combined with the current production process, the production process of the eight double frequency module and the low noise receiving module are introduced in detail by using the hybrid integrated circuit technology,and the processing as well as the test methods are also given in the paper. Finally, the test data of the module is analyzed, and the design of the front end component can be achieved.