Compact and Wide Stop Band Improved Stepped-Impedance Low Pass Filter Utilizing U-Slot

摘要

This paper presents a stepped-impedance low pass filter with a single open circuit stub resonator attached to its higher impedance elements. The low pass filter has shown improvement by adding T-shaped feed lines and U-slot at the single open circuit stub resonator. Simulated results exhibit sharp roll-off at 6.21GHz of 3dB cut-off frequency and creating transmission zero at around 7.13GHz with attenuation level -39.13dB near the pass band. On the other hand, the proposed filter has shown wide stop band bandwidth with rejection better than -10B from 6.88GHz up to 25GHz. The proposed filter layout has successfully shown and verified that good agreement between the theory and simulated results using full wave EM simulator.