A Reconfigurable Triple-Notch-Band Antenna Integrated with Defected Microstrip Structure Band-Stop Filter for Ultra-Wideband Cognitive Radio Applications

Abstract

A printed reconfigurable ultra-wideband (UWB) monopole antenna with triple narrow band-notched characteristics is proposed for cognitive radio applications in this paper. The triple narrow band-notched frequencies are obtained using a defected microstrip structure (DMS) band stop filter (BSF) embedded in the microstrip feed line and an invertedπ-shaped slot etched in the rectangular radiation patch, respectively. Reconfigurable characteristics of the proposed cognitive radio antenna (CRA) are achieved by means of four ideal switches integrated on the DMS-BSF and the invertedπ-shaped slot. The proposed UWB CRA can work at eight modes by controlling switches ON and OFF. Moreover, impedance bandwidth, design procedures, and radiation patterns are presented for analysis and explanation of this antenna. The designed antenna operates over the frequency band between 3.1 GHz and 14 GHz (bandwidth of 127.5%), with three notched bands from 4.2 GHz to 6.2 GHz (38.5%), 6.6 GHz to 7.0 GHz (6%), and 12.2 GHz to 14 GHz (13.7%). The antenna is successfully simulated, fabricated, and measured. The results show that it has wide impedance bandwidth, multimodes characteristics, stable gain, and omnidirectional radiation patterns.

Circular ring structured ultra-wideband antenna for wearable applications

“…To excite the antenna, microstrip transmission line feed technique is used in this design. Triangular slotted symmetric defected ground structure is incorporated with rectangular slit at the center of the DGS ground . The etched DGS on the ground plane perturbs the current path of the antenna and result in the change of capacitance and inductance.…”

“…Triangular slotted symmetric defected ground structure is incorporated with rectangular slit at the center of the DGS ground. 12 The etched DGS on the ground plane perturbs the current path of the antenna and result in the change of capacitance and inductance. The change in these parameters leads to miniaturization of the antenna size.…”

Multifunctional Antenna with Reconfigurable Ultra-Wide Band Characteristics

“…However, this interference could be minimized by creating notched response at these frequency bands. Notch structure could be realized by inserting U-shaped, C-shaped, -shaped slot, stepped impedance stub (SIS), stepped impedance resonators (SIR), SIS loaded hexagon stepped impedance resonators (HSIR), rectangular split ring, defected microstrip structure band stop filter (DMS-BSF), open ended T-shaped stub, etching spur slot, and half and quarter-wavelength strip in the form of resonator, either in the ground plane or in radiating plane itself [10][11][12][13], [15][16][17][18][19][20]. In most of these works, authors have reported reconfigurable UWB operation with single notch or multiple notches.…”

Design and Analysis of a Triple Stop-band Filter Using Ratioed Periodical Defected Microstrip Structure

“…After that, lots of DMSs have been reported for the stop-band filter or pass-band filter design [8]- [11], which includes two vertical narrow slots or spurline. Moreover, these DMS structures are also used for filtering antenna and stop-band filters [12]- [14]. However, most of them have only single or dual stop-band.…”