Sohrab Majidifar

In this article a novel microstrip wideband bandpass filter is designed using L-shaped resonator. The proposed resonator has been studied using a circuit model and the electromagnetic (EM) and circuit simulations are performed and their agreement verifies the validity of the circuit model. Designed filter has a sharp rejection and good passband performance. The stopband attenuation level of the proposed filter is more than 40 db at the left side and this parameter is 20 db at the right one. The proposed filter has a central frequency of 6.81 GHz and its passband has a fractional bandwidth of 0.2. In this filter, the harmonics are suppressed in the range of DC to 5.78 GHz and 7.81 GHZ to 14 GHz. The designed filter is fabricated on RO4003 with 20 mil thickness and dielectric constant of 3.38.