Title: Compact reconfigurable triple notch ultra-wideband bandpass filter for cognitive radio system
Authors: Janardan Sahay; Sanjay Kumar
Addresses: Department of Electronics and Communication Engineering, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India ' Department of Electronics and Communication Engineering, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India
Abstract: This paper introduces a compact ultra-wideband (UWB) bandpass filter (BPF) with two switchable external notch structures which avoids the interference between the UWB communication with worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN) systems, suitable for cognitive radio (CR) applications. The first external notch structure is modified C-shaped structure which generates a sharp rejection at 3.5 GHz to avoid interference with WiMAX system and second external notch structure is back to back T-shaped structure which creates sharp rejection notch bands at 5.2 GHz and 5.8 GHz frequencies for WLAN systems. The filter reconfiguration is achieved by varying the conductance of microstrip line. The response of the proposed structure shows sharp rejections at one WiMAX and two WLAN bands. The bandpass filter covers frequency of UWB system from 3.1 to 10.7 GHz having very low passband insertion loss. The proposed UWB BPF is designed, simulated, fabricated and tested to validate the results. A good agreement is achieved between simulation and experimental results.
Keywords: cognitive radio; notch band; reconfigurable filter; ultra-wideband; bandpass filter; interference; wireless local area network; WLAN; WiMAX.
International Journal of Computational Vision and Robotics, 2020 Vol.10 No.4, pp.337 - 344
Received: 06 Feb 2019
Accepted: 08 Jun 2019
Published online: 01 May 2020 *