Читать книгу Electrical and Electronic Devices, Circuits, and Materials - Группа авторов - Страница 51

Mehul Thakkar1,2*, Pravin R. Prajapati1,2 and Hitesh Shah2,3

1A.D.Patel Institite of Technology, New V V Nagar, Gujarat, India

2Gujarat Technological University, Gujarat, India

3G H Patel College of Engineeing and Technology, V V Nagar, Gujarat, India

Abstract

Due to the latest developments in multi-standard software defined radios and adaptive spectrum surveillance systems, over several years, the design of efficient high-frequency filters has become a popular and established research area in the field of application of electromagnetics and its component design. Without a doubt, the implementation of reconfigurable/tunable RF/microwave filtering components has been a trending area for recent research efforts in this field. Tunable/Reconfigurable filter design has been an active research topic due to challenges in tunable filters such as size reduction, selectivity, stop band reduction, insertion loss, center frequency tunability, bandwidth tuning, etc. Researchers are designing a filter to have the optimum parameter characteristics listed above.

The proposed work presents tunable microstrip filter with fractal DGS. Fractal DGS is used to reduce the size of the filter. The proposed filter is hairpin bandpass filter shape, which is designed for 3.5 GHz center frequency on the substrate of Rogers 3010 (ε_r = 10.2) with thickness of 1.27 mm. The hexagonal shape 3^rd iteration fractal DGS is introduced in ground plane, which results in the shifting of resonant frequency on lower frequency and improvement in return loss at the resonant frequency. The simulated and fabricated results with fractal DGS are presented and discussed. Tunability can be achieved using varactor diodes in fractal DGS structure. In the proposed work, tunability is simulated by using variable capacitors. The simulation and optimization of the proposed work are done using CST MICROWAVE STUDIO^® V. 2018.

Keywords: Microstrip filter, Tunable filter, Tunble filter with fractal DGS