Compact Microstrip Bandstop Filter for UWB Application

Abstract

In this paper, a novel Ultra-Wideband (UWB) Bandstop Filter (BSF) with five Transmission Zeros (TZ) and three Transmission Poles (TP) is presented. This filter is designed with a new type of resonator. Validation of the proposed filter with the lumped model is also investigated. Further, the transmission line circuit model of the filter is proposed, and consequently even and odd mode impedance is calculated analytically. Furthermore, a compact size of 16.8 mm × 14.98 mm (0.2λ_g × 0.18λ_g) is achieved by employing folded stubs. The proposed filter offers an Ultra-wide bandwidth of 7.5 GHz (2.9 –10.4 GHz) with a rejection depth of greater than 20 dB over the entire stopband. Moreover, the upper and lower skirt factors of 70 dB per GHz are achieved. A prototype of the proposed UWB BSF is fabricated and measured. Simulated and measured results are in good agreement, which validates the proposed design.

KEYWORDS:

• Even and Odd Mode
• Lumped Model
• Resonator
• Transmission Pole (TP)
• Transmission Zeros (TZ)
• Ultra-Wideband (UWB)

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Anil Rajput

Anil Rajput has received the BTech degree from the Electronics and Communication Engineering Department, UPTU, Lucknow, Uttar Pradesh, India, and the MTech degree in microwave electronics from the Department of Electronic Science, University of Delhi, New Delhi, India, and currently pursuing the PhD degree with the Department of ECE, PDPM IIITDM, Jabalpur, India. He worked as a JRF at PDPM IIITDM, Jabalpur, India, for 6 months. He has authored or co-authored over 20 research articles in international peer-reviewed journals and conferences. His current research interests include planar filters, reconfigurable circuits, meta-materials, and dielectric resonator antennas.

Biswajeet Mukherjee

Biswajeet Mukherjee has received the BTech degree from the ECE Department, Indraprastha University, Delhi, India, the MTech degree in microwave electronics from the Department of Electronic Science, University of Delhi, New Delhi, India, and the PhD degree from IIT Bombay, Mumbai, India. In 2014, he joined IIITDM, Jabalpur, India, as an assistant professor. He has authored or co-authored over 100 research articles in international peer-reviewed journals and conferences. His research interests include microwave engineering, DRA, filters, and metamaterials. He was a recipient of the Young Scientist Award at URSI GASS, 2014 and the IEI Young Engineering Award in 2016. Email: [email protected]