Design and development of circular filter using QSIW resonator

In this paper, we present a new Quarter-Mode Substrate Integrated Waveguide filter (QMSIW). A prototype of the proposed filter operating at 8.88 GHz was simulated under CST Microwave Studio and HFSS software. Return losses represent better than 20dB, while the simulated insertion losses represent 0.4dB. The simulated results of this filter show good agreement, with a size reduction of about 75 and 50 percent compared to the SIW and HMSIW filters, respectively. The proposed QMSIW filter has a wide bandwidth, low losses and a compact size, the total size being less than 12 mm × 6.7 mm × 0.508 mm without the feed lines.