Design of Miniaturized Half-Mode Substrate Integrated Waveguide Dual-Mode Dual-Band Filter for X and Ku Band Applications

With the advancement in technology, devices are required to have superior performance and be as small in size as possible, due to compactness of electronic devices. Most of these devices don't meet all criterias in one go. To enhance the criteria matching, in this work, two dual-band filters have been designed. The first one uses a SIW multi-mode resonator, two of which are magnetically coupled to form a dual-band filter. To achieve miniaturization, the full-mode multi-mode resonator is cut into two using the diagonal symmetry line. This results in a Half-Mode Substrate Integrated Waveguide (HMSIW) resonator used in the dualband second-order filter design. Using this HMSIW, a size reduction of 50% was achieved while operating at the same frequencies as in the full mode structure. This aids to reduce the size of microwave devices and increase in selectivity. Rogers substrate with a permittivity of 2.2 has been used to design the filter. Center frequencies of operation are 9.5 GHz and 13.8 GHz for the first and second pass-bands, respectively. The insertion loss recorded was 1 dB and 3 dB for the first and second pass-band, respectively.