[01] Abdessamed Chinig, Microwave Group, Faculty of Sciences and Techniques, Hassan 1st University, Settat, Morocco.

This paper presents a new design approach to achieve tunable microstrip low pass filters with compact size and good electrical performances. The proposed filter consists of a fork-shaped resonator coupled directly to two transmission lines. First, the low pass filter was designed to have a Chebyshev response with slightly wider bandwidth and high rejection. The second step of our design approach was to replace the transmission line in the middle of the circuit by a fork-shaped resonator. In order to control the tunability of the low pass filter, three identical capacitors was integrated in the extremities of the open circuited stubs. The simulation results obtained with schematic environment of (Advanced Design System) ADS solver show that it is possible to obtain a tunable low pass filter with low loss, high rejection, and wide stop band.

Fork-Shaped Resonators, Low-Pass Filter, Microstrip, Open Circuited Stubs, Tunable Capacitors

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