Three-axes radiating millimeter-wave antenna-in-package design for mobile devices

Abstract

As the proportion of mobile devices such as smartphones and tablet PCs increasing in personal life, various functions and technologies are being integrated into mobile devices. In particular, attention has recently been focused on applications using virtual reality such as VR HMD and AR Glass. High-speed wireless communication is indispensable for the use of mobile devices that process high-capacity data. Because high-speed data communication is possible with a wide bandwidth of 9 GHz and the size of the system can be reduced with a high frequency, various attempts are being made to apply wireless communication using the 60 GHz band to mobile systems. Research on antenna-in-package technology has many difficulties due to the problems of radiation distortion, efficiency and coverage degradation due to interference from space limitation and complex internal structures of mobile devices. Therefore, in this paper, a new antenna-in-package structure (AiP) is proposed. The 3-axes radiating AiP has a compact structure suitable for a mobile communication, wide coverage, and high radiation efficiency. This paper is composed of a total of 6 chapters. In chapter2, vertically polarized Yagi-Uda antenna is presented. The proposed antenna reduces the size of the antenna by using the image effect of the ground plane. In addition, it is easy to integrate into mobile devices because end-fire radiation is possible with vertically polarized field that are insensitive to substrate interference. In chapter 3, a compact vertically polarized end-fire antenna that implemented as a multi-layered horn antenna is presented. A horn aperture is configured by using metal patterns and a number of via on a multilayer substrate, and a small radiator is applied for vertically polarized radiation. As a result, the antenna is reduced effect of interference and increase radiation efficiency. In Chapter 4, a new multibeam AiP structure is presented. The AiP is able to radiate 3-axes by integrating a broadside horn antenna and three end-fire antennas introduced in Chapter 3 into a single multilayer substrate. The AiP reduces signal loss by applying efficient packaging method that allows integration of RFIC and radiate 3-axes by integrated four antennas into a single substrate with low interference through shielding structures composed of metal patterns and vias. In chapter 5, two directional 1x4 antenna array in package is presented. The compact end-fire antenna and broadside antenna introduced in chapters 3 and 4 are arranged in an array structure in two directions most commonly used to utilize various mobile devices. The antenna array in package increase utilization and coverage through beamforming technology. At last, in chapter 6, the paper is summarized and concluded.