Bandpass filter are of very high importance when considering features such as signal transmission and wireless communication. The use of Microstrip technology offers us a very compact realization of a microwave filter thereby reducing the filter size and output parameters. This project proposes a capacitor tuned microstrip coupled bandpass filter (BPF) loaded with parallel coupled microstrip line with capacitors connected in the middle in order to enhance tuning of the bandpass filter instead of free ends. This configuration enhances the tunability of the suggested BPF by varying the values of the capacitances inserted in the circuit, which leads to a wide tuning range even with a small capacitance values. Therefore, a wide tuning range can be obtained by employing low capacitance values with which a tunable bandpass filter can be achieved. As a result, the proposed tunable BPF can keep nearly constant bandwidth over the wide tuning range. Based on the requirement of the operating frequency the bandpass filter can be tuned for the particular frequency thereby enhancing the band selectivity character in the design.
Volume 11 | 04-Special Issue
Pages: 2409-2417