Design of a Compact Microstrip Band Pass Filter for IoT and S-Band Radar Applications

This paper presents firstly the literature review and then investigates the design, simulation, and performance analysis of a compact microstrip bandpass filter (BPF) for wireless communication, IoT, and radar systems as candidate for TWIN OPEN LOOP RESONATORS in our future studies of filter and diplexers. Using ROGER RT (RO3003), an open-loop square with two SIRS at the top of the resonator structure is investigated for the filter, which is optimized to operate at the center frequency of 3,82 GHz with an external quality factor of 57,88. Regarding S-parameter results, the performance is good, with an insertion loss of 0,41 dB, while a high return loss is achieved at 21,66 dB. Such characteristics guarantee good selectivity and low signal distortion at an upper band of 83,74 dB /GHz with a transition band of 0,269 GHz. The proposed BPF has a transmission zero of 71,53 dB at 4,427 GHz with a compact size of 18 mm × 18 mm.