High Gain and Compact Antipodal Tapered Slot Antennas for Broadband Millimeter Wave Applications

Abstract

In recent years, the use of high gain directional antennas for millimeter wave applications such as high-resolution imaging, automotive radar and high-definition video is increasing day by day. The antenna employed for such applications should have high directivity, high gain, wide bandwidth and small size. One of the most often used directional antennas for these applications is the horn antenna. However, it is expensive to manufacture, relatively large and bulky. The Vivaldi antenna, also known as Tapered Slot Antenna (TSA), has emerged as a potential alternative for these applications. The tapered structure of the antenna produces traveling waves in the end-fire direction and provides broad bandwidth, high gain and maximum radiation with linear polarization. However, there are a few challenges in designing TSAs such as improving the antenna gain without increasing the area while maintaining stable radiation pattern. Another design challenge is avoiding the use of external circuitry for the system-level integration of the TSA for space-constrained applications. Therefore, the primary aim of this research is to propose design techniques for achieving a low-profile antipodal tapered slot antenna with improved gain and radiation characteristics. In addition, antipodal tapered slot antenna integrated with bandpass filter configurations are designed to achieve easy system-level integration. With the achieved performance enhancement, the proposed antennas are suitable to be deployed in high resolution wideband millimeter wave imaging applications.