Implementation and Investigation of a Compact Circular Wide Slot UWB Antenna with Dual Notched Band Characteristics using Stepped Impedance Resonators

A coplanar waveguide (CPW) fed ultra-wideband (UWB) antenna with dual notched band characteristics is presented in this paper. The circular wide slot and circular radiation patch are utilized to broaden the impedance bandwidth of the UWB antenna. The dual notched band functions are achieved by employing two stepped impedance resonators (SIRs) which etched on the circular radiation patch and CPW excitation line, respectively. The two notched bands can be controlled by adjusting the dimensions of the two stepped impedance resonators which give tunable notched band functions. The proposed dual notched band UWB antenna has been designed in details and optimized by means of HFSS. Experimental and numerical results show that the proposed antenna with compact size of 32 × 24 mm2, has an impedance bandwidth range from 2.8 GHz to 13.5 Hz for voltage standing-wave ratio (VSWR) less than 2, except the notch bands 5.0 GHz - 6.2 GHz for HIPERLAN/2 and IEEE 802.11a (5.1 GHz - 5.9 GHz) and 8.0 GHz - 9.3 GHz for satellite and military applications

A Coplanar Waveguide Fed Hexagonal Shape Ultra Wide Band Antenna with WiMAX and WLAN Band Rejection

In this paper, a coplanar waveguide (CPW) fed hexagonal shape planar antenna has been considered for ultra-wide band (UWB). This antenna is then modified to obtain dual band rejection. The Wireless Local Area Network (WLAN) and Wireless Microwave Access (WiMAX) band rejections are realized by symmetrically incorporating a pair of L-shape slots within the ground plane as well as a couple of I-shape stubs inserted on the bottom side of radiating patch. The proposed antenna has stop bands of 5.05-5.92 GHz and 3.19-3.7 GHz while maintaining the wideband performance from 2.88 - 13.71 GHz with reflection coefficient of ≤ -10 dB. The antenna exhibits satisfactory omni-directional radiation characteristics throughout its operating band. The peak gain varies from 2 dB to 6 dB in the entire UWB frequency regions except at the notch bands. Surface current distributions are used to analyze the effects of the L-slot and I-shape stub. The measured group delay has small variation within the operating band except notch bands and hence the proposed antenna may be suitable for UWB applications

A Tri-band-notched UWB Antenna with Low Mutual Coupling between the Band-notched Structures

A compact printed U-shape ultra-wideband (UWB) antenna with triple band-notched characteristics is presented. The proposed antenna, with compact size of 24×33 mm2, yields an impedance bandwidth of 2.8-12GHz for VSWR<2, except the notched bands. The notched bands are realized by introducing two different types of slots. Two C-shape half-wavelength slots are etched on the radiating patch to obtain two notched bands in 3.3-3.7GHz for WiMAX and 7.25-7.75GHz for downlink of X-band satellite communication systems. In order to minimize the mutual coupling between the band-notched structures, the middle notched band in 5-6GHz for WLAN is achieved by using a U-slot defected ground structure. The parametric study is carried out to understand the mutual coupling. Surface current distributions and equivalent circuit are used to illustrate the notched mechanism. The performance of this antenna both by simulation and by experiment indicates that the proposed antenna is suitable and a good candidate for UWB applications

Wideband and UWB antennas for wireless applications. A comprehensive review

A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account. The performances of small, low-profile, and dielectric resonator antennas are illustrated paying particular attention to the application areas concerning portable devices (mobile phones, tablets, glasses, laptops, wearable computers, etc.) and radio base stations. This information provides a guidance to the selection of the different antenna geometries in terms of bandwidth, gain, field polarization, time-domain response, dimensions, and materials useful for their realization and integration in modern communication systems

Compact Printed CPW-fed UWB antenna with SRR and Quarter wavelength slot with dual band-notched characteristic

Volume 2 Issue 3 (March 2014

A Review: Circuit Theory of Microstrip Antennas for Dual-, Multi-, and Ultra-Widebands

In this chapter, a review has been presented on dual-band, multiband, and ultra-wideband (UWB). This review has been classified according to antenna feeding and loading of antennas using slots and notch and coplanar structure. Thereafter a comparison of dual-band, multiband, and ultra-wideband antenna has been presented. The basic geometry of patch antenna has been present along with its equivalent circuit diagram. It has been observed that patch antenna geometry for ultra-wideband is difficult to achieve with normal structure. Ultra-wideband antennas are achieved with two or more techniques; mostly UWB antennas are achieved from coplaner structures

Investigation into the design of ultra-wideband (UWB) and multi-band antennas

University of Technology, Sydney. Faculty of Engineering.The rapid development of high speed wireless communications as well as other applications such as microwave imaging place extraordinary demands on spectrums for which ultra-wideband (UWB) and multi-band, e.g.: dual-band, techniques are useful. These UWB and multi-band services require UWB and multi-band antenna designs. Motivated by these applications, we first carried out the investigations on the family of square plate monopole (SPM) antennas for UWB applications. The family of square plate monopole (SPM) UWB antennas yields quite attractive features, viz.: ease of fabrication and freedom of dielectric material selection. Next, we considered the use of coplanar waveguide (CPW) fed printed UWB antenna for compact, body-worn applications. We investigated the antenna performance using empirical optimisation. The work on CPW-fed printed antennas has led to the development of multi-band antennas also. For UWB antennas, we have first considered the modifications of well know square plate monopole (SPM) antennas. Our approach differs from other similar approaches on SPM antennas published in the literature. We have introduced symmetrical modifications to both bottom and top portions of the SPM antenna element. This has led to the development of these types of symmetrically modified SPM antennas, viz.: symmetrically beveled SPM (SB-SPM) antenna, symmetrical semi-circular base SPM (SSCB-SPM) antenna and symmetrically notched SPM (SN-SPM) antenna. All these antennas have been empirically optimised using Feko® and the theoretical and experimental results are provided, in the point of view of reflection coefficient, radiation characteristics, phase response of antenna transfer function and time domain response. For better suiting the compact and body-worn UWB applications, we have investigated the design of CPW-fed printed antenna. We have explored the antenna characteristics using empirical optimisation. The theoretical and experimental results for the completed CPW-fed printed antenna are provided, in the point of view of reflection coefficient, radiation characteristics, phase response of antenna transfer function, group delay and time domain response. Lately, for multi-band antennas, we have investigated the design of multi-band printed antennas, which are fed by CPW, to suit emerging design requirements. Two CPW-fed dual-band printed antennas for GSM and DCS/PCS as well as DCS/PCS and IEEE 802.11b applications are proposed, which have C-shape and T-shape structures respective1y. The theoretical and experimental results for these antennas are provided, in the point of view of reflection coefficient and radiation characteristics. Due to the use of substrate material for the designs of UWB CPW-fed printed antenna as well as C-shaped and T-shaped dual-band CPW-fed printed antennas, the effects of substrate material tolerances on UWB characteristics and dual-band characteristics are investigated. Furthermore, as these UWB and dual-band CPW-fed printed antennas are the promising candidates for wireless body-worn applications, which include wireless body area network (WBAN), the interactions between them and lossy material, such as human tissue, are investigated, which might help to decide the suitability of them for wireless body-worn applications