Design and implementation of a controllable phase shifter using substrate integrated waveguide

In this study, a controllable phase shifter using substrate integrated waveguide (SIW) technique is designed and implemented. The proposed phase shifter consists of a SIW section with a number of PIN diodes buried within the substrate. The phase shifting is achieved by changing the loading of the waveguide and that loading is controlled by turning the buried diodes ON and OFF. As a proof of concept, a prototype has been fabricated where four NIP diodes were used. Simulation and experimental results were in good agreement and a maximum differential phase of 45° has been achieved with good performance regarding return loss and insertion loss.