Reconfigurable SIW Phase Shifter Based on Parallel Stubs loaded with Surface Mount PIN Diodes

This paper proposes a robust approach for developing a new class of electrically reconfigurable phase shifter. This design employs via posts on SIW technology in conjunction with surface mount PIN diodes. To ensure optimal performance over the intended frequency band in a space-efficient manner, the transmission line is based on a substrate integrated waveguide (SIW) which offers superior low-loss properties. Additionally, PIN diodes are integrated into the SIW line using transverse coplanar waveguide (CPW) stubs. The efficiency of the proposed design method and the practicality of incorporating an innovative biasing circuit on a single layer without requiring additional wire bonding layers is demonstrated in the experimental prototypes outlined in this paper. This approach facilitates a scalable and modular device design. The principle of achieving such high-quality circuits is detailed and is also confirmed by experimental and theoretical results which are in good agreement up to at least 6 GHz, validating the design procedure and demonstrating that complex circuit functions can be achieved with relatively inexpensive compact structures. The proposed structure has potential applications in time-varying systems, communication receiving sections, and beamforming networks.