Antenna array in eWLB for 61 GHz FMCW radar

In this article we present an antenna array concept in embedded wafer level ball grid array (eWLB) package for mm-wave applications. The eWLB package has a excellent performance for high frequency and the additional fan-out area around the silicon chip enables the realization of passives and antennas. Moreover, integration of the antenna in package increases the efficiency and reduces cost. For some applications a single antenna in package is unable to achieve the required gain and directivity. Combining several antenna elements as an array in a package can be a possible solution. A two elements differential dipole antenna array in an 8 mm × 8 mm eWLB package at IMS (Industrial, Medical and Scientific) band about 61 GHz is analyzed and successfully implemented. A 100 Ω differential feeding system is designed for the array. The measured reflection coefficient is -25 dB and the designed antenna array has a gain of 11 dB and radiates in broadside.