Design and Testing of a Broadband Microstrip Line-Empty SIW Transition for 5G Applications

Abstract

This paper presents a new broadband transition between microstrip and empty substrate integrated waveguide (ESIW) over 23–29 GHz band. In the proposed work, the design is initially implemented to use SIW and combined with three layers of the substrate such as top, bottom, and middle. One side without a cladding conductor and the other side just a conductor are implemented for the top and bottom layers. Simultaneously, the middle layer is used as air instead of the lossy dielectric to limit the loss. In order to improve matching, two shorting pins are placed on two sides of the middle layer. It can be found that the shorting pin's diameter and position plays a crucial role in providing broadband impedance bandwidth and low overall losses. Laboratory prototype of the structure is experimentally measured to validate the claim and the theoretical results. This transition finds suitable application for 5G communications.