Kemal GüvenliSibel Yeni̇KayaMustafa Seçmen2025-10-06202313921215, 202957311392-12152029-573110.5755/j02.eie.31628https://www.scopus.com/inward/record.uri?eid=2-s2.0-85182572923&doi=10.5755%2Fj02.eie.31628&partnerID=40&md5=e057f48a912439adad8b218b343dbe69https://gcris.yasar.edu.tr/handle/123456789/8507This study presents an original parallel connected hybrid microstrip-substrate integrated waveguide (PCHM-SIW) bandstop filter. A low-pass filter implemented on a microstrip structure and a SIW-based high-pass filter are connected in parallel to each other. In this way the aim is to obtain a bandstop filter in the novel hybrid design. The parallel connected hybrid microstrip-substrate integrated waveguide (PCHM-SIW) bandstop filter is synthesised simulated and produced. The effects of connecting filters in parallel are discussed. It is seen from the results of CST Studio Suite simulation that PCHM-SIW bandstop filter has a bandwidth of 2.85 GHz and a center frequency of 4.26 GHz. The frequency change rate of the center frequency between simulation and measurement is 7.02 % where it is just 3.76 % for the deviation in bandwidth. The results of the simulation and those of the measurement are close to each other. These results converge to ideal analytical results. © 2024 Elsevier B.V. All rights reserved.EnglishHybrid Bandstop Filter, Microstrip, Parallel Integration, Substrate Integrated Waveguide, X-bandArticle