# Miniaturized Compact Reconfigurable Half-Mode SIW Phase Shifter with PIN Diodes
## 3 Results and Discussion of Varied Solutions
Figure 7: A fabricated HM-SIW phase shifter that can be easily integrated with other microwave components due to its compact, modular, and miniaturized features. Figure 8: Scattering parameters versus frequency for two states: (**a**) all diodes OFF, and (**b**) all diodes ON. Reflection coefficients for port 1 (S11), port 2 (S22), and the coupling parameter between the ports (S21) are obtained. Simulation software charts are in solid colors, and the experiment is shown in dashed lines. State 000 is the situation with all diodes OFF, while state 111 is three diodes ON at the same time. Figure 9: The achieved phase shift quantities are presented using the proposed reconfigurable structure with three parallel diode posts integrated with a HM-SIW transmission line. Comparisons are made between the results of two concrete simulations and experiment solutions: (**a**) the first phase range of 45\({}^{\circ}\) to 70\({}^{\circ}\); (**b**) the medium phase range of 30\({}^{\circ}\) to 45\({}^{\circ}\); and (**c**) the primary phase steps of 0\({}^{\circ}\) to 30\({}^{\circ}\). In order to compare the achieved results with similar phase shifter designs in the literature, Table 1 was prepared. The proposed structure has a promising configuration compared to recent phase shifter designs in the literature. In addition to the tunable states (seven normalized modes), the DC biasing of PIN diodes is integrated into a similar layer as the RF signal. This feature eliminates the need for an extra bias layer (preventing multilayer designs). Furthermore, the half-mode design decreases the width of the SIW phase shifter, which makes it an ideal device for modular and integrated systems. Miniaturized size and enhanced DC biasing technology enable a reliable, cost-effective electronic component that can be integrated into a package. As an example, the proposed system can be applied to a sensing antenna for the phase engineering section. Beam steering systems require compact phase shifters. With a phase shifter, it is possible to realize a high-resolution detective system for applications such as automatic radar sensors. Another application of this innovative phase shifter is for time-varying surfaces. Furthermore, a revised model is simulated using simulation software in Appendix A to illustrate the capabilities of the proposed HM-SIW structure. It is possible to cascade two or more phase shifters to generate higher phase shift values. Signal loss happens at port connections and transitions, so cascading more phase shifter components does not generate more loss. This expanded design is included in Appendix A of the simulation software. The total size of the redesigned model will increase by 41%. Moreover, a parametric study is provided in Appendix B. The parametric study covers the nonlinearity and variation of PIN diode characteristics, including the equivalent parallel circuit models. In this case, the diode parameters such as resistance, inductance, and capacitance were tuned to further investigate their effects on the scattering parameters of the HM-SIW. As well as using full wave simulation software to analyze the compact structure, circuit simulation software is used to study the different circuit elements modeling the diodes.