Circular Split Ring Resonator (C-SRR) Array Integrated Frequency-Notched Horn-Filtenna With Wide and Strong Rejection Band

Sandip Sankar Roy,Debdeep Sarkar,Naresh Kumar Mallenahalli,Chinmoy Saha

doi:10.1109/access.2021.3069701

Abstract

Linear-array of circular split ring resonators (C-SRR) integrated wideband notched filtering horn antenna with very strong rejection-band is proposed in this article. The linear C-SRR array, consisting of 3-sub arrays each having 4 identical C-SRR-elements, is printed on a dielectric substrate and is integrated into the throat or waveguide-section of the standard X-band horn (Narada 641). Staggered arrangement of the multiple C-SRRs based in-line filter contributes to the wideband notch filtering response with measured rejection band (S11 < 3-dB) of 315 MHz in proposed horn-filtenna. The realized horn-filtenna yields co- and cross- polar peak gain suppression of 35.42 dB and 24.6 dB at and around the centre of notch-band (9.8 GHz) while at the pass band of the C-SRR filter, the proposed antenna inherits the impedance and radiation characteristics of the standalone horn antenna. The proposed technique is simple, easy to integrate and can be used to eliminate adjacent band noise/interference for faithful reception of data without using any additional filter section.

Highlights

Mitigation of noises and/or interferences from adjacent channels/bands is one of the key requirements in any practical receiving system for improved efficiency, increased signalto noise ratio and overall performance
Choice on the number of sub-arrays, circular split ring resonators (C-Split ring resonator (SRR)) elements in the sub-arrays and the dimension of the C-SRRs are optimally decided based on, i) centre frequency in the rejection band, ii) rejection bandwidth and iii) amount of gain suppression targeted by the in-line filter when integrated with the horn antenna
Systematic studies and realization of the WG-based filter section, followed by the integration of the same in the throat region of a standard gain horn reveals a very strong rejection band of 315 MHz spanning from 9.635 GHz to 9.95 GHz

Summary

Introduction

Mitigation of noises and/or interferences from adjacent channels/bands is one of the key requirements in any practical receiving system for improved efficiency, increased signalto noise ratio and overall performance. Frequency-notched wide/UltraWide Band (UWB) antenna, thanks to its inbuilt notch-filtering functionality, is a potent solution for this purpose [1], [2] Various notching techniques, such as, i) employing shaped slots, ii) embedding parasitic resonators adjacent to the radiators, iii) integrating (SRR) along the feedline, and iv) combination of (i)-(iii), have been adopted over last few years to realize single/multi-notched UWB antennas [3]–[16]. Most of these designs use printed monopole as the reference radiator for realizing frequency notched UWB response [3]–[7]. A substrate-integrated waveguide cavity based horn filtenna with integrated filtering response is demonstrated in [6]

Methods

Conclusion