Empty substrate integrated waveguide technology for E plane high‐frequency and high‐performance circuits

Angel Belenguer,Eduardo Artal,Héctor Esteban,Juan Luis Cano,Vicente E Boria

doi:10.1002/2016rs006181

Abstract

AbstractSubstrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential of low cost, easy manufacturing, integration in a circuit board, and higher‐quality factor than planar circuits. A first suite of SIC where the waves propagate through dielectric have been first developed, based on the well‐known substrate integrated waveguide (SIW) and related technological implementations. One step further has been made with a new suite of empty substrate integrated waveguides, where the waves propagate through air, thus reducing the associated losses. This is the case of the empty substrate integrated waveguide (ESIW) or the air‐filled substrate integrated waveguide (air‐filled SIW). However, all these SIC are H plane structures, so classical H plane solutions in rectangular waveguides have already been mapped to most of these new SIC. In this paper a novel E plane empty substrate integrated waveguide (ESIW‐E) is presented. This structure allows to easily map classical E plane solutions in rectangular waveguide to this new substrate integrated solution. It is similar to the ESIW, although more layers are needed to build the structure. A wideband transition (covering the frequency range between 33 GHz and 50 GHz) from microstrip to ESIW‐E is designed and manufactured. Measurements are successfully compared with simulation, proving the validity of this new SIC. A broadband high‐frequency phase shifter (for operation from 35 GHz to 47 GHz) is successfully implemented in ESIW‐E, thus proving the good performance of this new SIC in a practical application.

Highlights

Substrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential
The half mode substrate integrated waveguide (HMSIW) Hong et al [2006] reduces the size of the SIW to the half, by exploiting the fact that there is a symmetry plane along the propagation direction that is equivalent to a magnetic wall
The proposed structure for the transition from microstrip to empty substrate integrated waveguide (ESIW)-E is inspired in the typical solution for the transition from coaxial line to rectangular waveguide, usually known as “launcher.” In this transition the waveguide is short circuited in one of its ends and, approximately at λ∕4 from the short circuit, the inner conductor of the coaxial line is inserted through a hole mechanized in the upper wall of the waveguide

Summary

Introduction

Substrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential. The half mode substrate integrated waveguide (HMSIW) Hong et al [2006] reduces the size of the SIW to the half, by exploiting the fact that there is a symmetry plane along the propagation direction that is equivalent to a magnetic wall The advantage of this new concept of substrate integrated waveguide, when compared with classical planar circuits, is that it is low cost and easy to manufacture with standard printed circuit board (PCB) machinery. As the HSIW, the lateral walls are a row of metallized via holes in the main substrate In this case the air filled SIW is manufactured with standard PCB substrate, and transitions are developed which connect the air filled SIW with accessing microstrip ports. Measurements are shown that well prove the potential of the new ESIW-E

Design of the Transition From Microstrip to ESIW-E

Manufactured Back-to-Back transition

Conclusion