應用於77GHz車用短距雷達之平衡式饋入寬頻寬波束陣列天線

Abstract

本論文將提出一個應用於77GHz汽車防撞警示雷達短距(Short-Range, SR)之寬頻寬波束天線架構。其天線使用頻段為77到81GHz，可提供本車道近距離及大範圍角度偵測。短距天線基本架構為一陣列天線 (Array Antenna)，陣列天線末端為嵌入式微帶天線(Insert Patch Antenna)，達到較寬頻的阻抗匹配，並利用平衡式饋入架構，增加天線增益的頻寬，最後利用雙寄生元件效應，使天線的波束寬度可以涵蓋-45度到45度，達到寬波束之需求，並改善天線的阻抗匹配及輻射效率，提升天線增益。

In this thesis, we proposed a broadband and wide-beam short-range antenna structure used in the 77GHz automotive collision warning radar. The bandwidth of the short-range antenna is from 77 to 81GHz. The antenna can detect short-range distance and wide angle of view from once own lane. The basic structure of the short-range antenna is an array antenna. In the end of the array antenna is an insert patch antenna which can provide broadband impedance matching. With the corporate feeding, the gain bandwidth can be wider. Finally, by using dual parasitic elements, not only the antenna beamwidth can cover from -45 degrees to 45 degrees but also the impedance matching and radiation efficiency can be improved to enhance antenna gain.