Design, implementation and optimization of substrate integrated waveguide filters to be used in microwave frequencies

In this study; Microstrip-SIW (Subsrate Integrated Waveguide) filters that can be used in satellite communication, radar and next generation 5G technologies have been analyzed, simulated and produced in the laboratory. A high pass SIW filter structure and a low pass microstrip filter structure are combined to obtain a band pass or band stop filter. Filter structures are integrated with each other by cascade or parallel connection. The bandwidth of the hybrid filter can be easily determined by the cut-off frequencies of the low pass and high pass filters. This hybrid method offers flexibility in design and manufacturing. The transparent and flexible design method, which is different from traditional and complex filter designs, has made the filter more understandable and forward-looking. In this context, the symmetric windowed SIW filter; X-Ku band pass substrate integrated waveguide filter; Microstrip-SIW modular broadband band stop filter; Cascade-connected hybrid Microstrip-SIW band pass filter and parallel connected hybrid Microstrip-SIW band stop filter designs are presented, simulated and implemented. Obtained results were evaluated and interpreted comparatively. Five different optimization methods were used to improve the quality factor of the cascade-connected hybrid Microstrip-SIW band pass filter. As a result of the optimization study on the microstrip-SIW band pass filter, the quality factor value of the filter was increased from 2.75 to 8.85.