Universal low-cost Transmitarray Antenna Design at 61 GHz for Beam Steering with different Feed Antennas

This paper presents the design and characterization of an universal low-cost transmitarray antenna operating at 61 GHz. The transmitarray design is based on unit cells with 1 bit phase resolution. A 180deg phase shift is introduced by an element rotation on the bottom side of the unit-cell. Two separate layers of a RO4350B substrate are utilized to ensure a low-cost fabrication. One dimensional beam steering in azimuth is performed from 0deg to 70deg by 8 different transmitarrays. A selective laser sintered horn antenna and three different embedded wafer level ball grid array (eWLB) package antennas have been used as feed demonstrating the universal application of the designed transmitarray antennas. Additionally, two transmitarrays with different beam steering angle combinations in azimuth and elevation have been designed and successfully characterized with both horn antenna and package antenna to validate the 2D beam steering capability of the design.