A CPW-fed stepped slot UWB antenna for MIMO/diversity applications

2015 ◽  
Vol 9 (1) ◽  
pp. 151-162 ◽  
Author(s):  
Raj Kumar ◽  
Neha Pazare

An ultra-wideband (UWB) slot antenna for diversity applications is introduced. The overall structure of the antenna consists of two similar coplanar waveguide (CPW)-fed stepped rectangular slots placed in an orthogonal position. The slots are asymmetric with respect to their placement in the ground plane. The CPW feeds are double stepped and terminated on hexagonal patches for better impedance matching. A wide impedance bandwidth (measured) from 3 to 12 GHz with an isolation better than 15 dB is obtained with this antenna. To improve the isolation, the design is modified and an I-shaped slot strip is introduced between the two slot antennas. With this, the isolation is brought about 25 dB of most of the band, while the impedance bandwidth remains the same (2.8–12 GHz for port 1, measured and 2.9–12 GHz for port 2, measured). The far-field radiation patterns are also measured and a peak gain of about 5 dBi is obtained. Finally, the diversity parameters such as envelope correlation coefficient and capacity loss are calculated and found to have low values. The antenna is expected to be useful for UWB diversity applications with good isolation.

2020 ◽  
Vol 8 (5) ◽  
pp. 3988-3990

In this paper, A coplanar waveguide (CPW) ultra-wideband(UWB) antenna is designed, analyzed and simulated by computer simulation technology(CST). The proposed antenna is fabricated on FR-4 dielectric substrate. A microstrip feed line is used to excite the antenna.The ground plane is slotted to improve the impedance bandwidth (BW). Here, a rectangular patch is used as radiator and two corners out of four are truncated to improve impedance matching and UWB characterization.This antenna satisfies UWB characteristics like VSWR<2, Return loss(S11)<-10 dB,Gain<5dB and the antenna is operating within the frequency range of 1.59 to 11.87 GHz range which covers whole ultra wideband i.e. 3.1 to 10.6 GHz range.


2014 ◽  
Vol 7 (5) ◽  
pp. 571-577
Author(s):  
Raghupatruni Venkat Siva Ram Krishna ◽  
Raj Kumar ◽  
Nagendra Kushwaha

A compact slot antenna for high-gain ultra wideband applications is presented. The slot is asymmetrically cut in the ground plane and is a combination of two rectangles. A hexagonal patch with two stepped coplanar waveguide-feed is used to excite the slot. The capacitive reactance of the hexagonal patch is neutralized by the inductive reactance created by the asymmetric slot and results into wider impedance matching. The measured impedance bandwidth of the proposed antenna is 11.85 GHz (2.9–14.75 GHz). The radiation patterns of the proposed antenna are found to be omni-directional in the H-plane and bi-directional in the E-plane. To enhance the gain of the antenna, a compact three-layer frequency selective surface (FSS) is used as a reflector. The overall thickness of the FSS is 3.5 mm. There is 4–5 dBi improvement in antenna gain after application of the FSS. The measured and simulated results are in good agreement.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Qiang Wang ◽  
Yan Zhang

A new compact ultra-wideband (UWB) antenna with triband-notched characteristics is presented. The structure of the proposed antenna is simple and symmetric. A modified ground is introduced to obtain a wide impedance bandwidth of 2.9–13.4 GHz withS11<-10 dB. By inserting two arc-shaped slots in the radiation patch, two sharp bands of 3.3–3.7 GHz and 5.15–5.35 GHz are notched. The notch band of 7.25–7.75 GHz is achieved by etching a U-shaped slot in the ground plane. The notched bands can be controlled, respectively, while the characteristics of the proposed UWB antenna almost keep completely unchanged at the unnotched frequencies. Equivalent circuit models, surface current distributions, and input impedance are applied to analyze the principle of the proposed UWB antenna. Parametric studies are given. Simulated and measured results show that the proposed antenna has good impedance matching, stable radiation patterns, and constant gain.


2015 ◽  
Vol 77 (10) ◽  
Author(s):  
Raimi Dewan ◽  
Mohamad Kamal A Rahim ◽  
Mohamad Rijal Hamid ◽  
M.H. Mokhtar ◽  
M.F.M. Yusoff

In this paper, an Ultra Wideband (UWB) antenna is presented. The antenna radiating patch is circular in shape with coplanar waveguide (CPW) feeding technique. The proposed chamfering to the outer edges of the ground plane successfully widens the -10 dB impedance bandwidth of the antenna to cover from 1.92 GHz up to 15.16 GHz (correspond to 155% fractional bandwidth). The antenna gain varies from 2 to 5 dB over the operating band. Parametrical studies have been conducted for four different conditions of the ground plane; without chamfering, chamfering on the inner edges, chamfering on the outer edges and both chamfering of inner and outer edges. The effects of distinguished chamfering conditions to antenna performance are analyzed.  The measured and simulated results for reflection coefficients and radiation patterns (2.45 GHz, 3.5 GHz and 5.8 GHz) are presented. The corresponding realized gains are 2.14 dB, 2.85 dB and 3.4 dB respectively. The measured results satisfactorily agreed with the simulated ones. The antenna is 8 - 37 % wider bandwidth than previous research.


2012 ◽  
Vol 195-196 ◽  
pp. 13-16
Author(s):  
Wen Bo Zeng ◽  
Jia Zhao ◽  
Bao Zhong Ke ◽  
Qi Qi Wu

An ultra-wideband (UWB) printed antenna with dual band-notched characteristic is presented in this paper. The proposed antenna is composed of a semi-circular patch fed by a tapered coplanar waveguide (CPW) and an unclosed ground plane, which are printed onto the same side of a FR4 printed circuit board (PCB) with an overall size of 30 mm × 30 mm × 1.5 mm. By embedding a simple arc-shaped slot in the patch and adding a T-shaped strip on the top of the patch, two notched frequency bands for rejection of WiMAX and WLAN system can be realized. The characteristics of the proposed antenna are investigated by using the software HFSS and validated experimentally, both simulated and measured results show that the proposed antenna prototype achieves good impedance matching over an frequency band from 2.1011.40 GHz for VSWR2 with two notched bands over the frequency range of 5-5.95 GHz and 3.1-3.9 GHz. Furthermore, a relatively stable gain and suitable radiation patterns are also achieved in both lower and upper UWB frequency band.


2021 ◽  
Vol 36 (6) ◽  
pp. 788-795
Author(s):  
Dalia Elsheakh ◽  
Osama Dardeer

This article presents a 2×1 CPW ultra wideband rectangular slot antenna array (UWB-RSAA) with a modified circular slot shape to support a high data rate for wireless communications applications. The proposed antenna array dimensions are 0.7λ×0.8λo×0.064λo at the resonant frequency 1.8 GHz. It is fabricated on Rogers RO4003 substrate and fed by using a coplanar waveguide (CPW). A graphene layer is added on one side of the substrate to realize frequency reconfigurability and improve the array gain. The proposed array acquires -10 dB impedance bandwidth of the RSAA that extends from 1.7 GHz to 2.6 GHz, from 3.2 to 3.8 GHz, and from 5.2 GHz to 7 GHz. The proposed array achieved a realized peak gain of 7.5 dBi at 6.5 GHz at 0 Volt bias with an average gain of 4.5 dBi over the operating band. When the graphene bias is increased to 20 Volt, the antenna bandwidth extends from 1 GHz to 4 GHz and from 5 to 7 GHz with a peak gain of 14 dBi at 3.5 GHz and an average gain of 7.5 dBi. The linearly polarized operation of the proposed array over the operating bands makes it suitable for short-range wireless communications .


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Tamer Aboufoul ◽  
Akram Alomainy ◽  
Clive Parini

A compact reconfigurable and notched ultra-wideband (UWB) tapered slot antenna (TSA) is presented. The antenna reconfiguration operation principle relies on 2 mechanisms: in the first mechanism a resonator parasitic microstrip line electrically coupled to the TSA is used to notch the TSA at a specific frequency and the second mechanism relies on changing the input impedance matching of the antenna by means of changing the length of a stub line extended from an additional tiny partial ground on the back side of the antenna. The reflection coefficient, radiation patterns, and gain simulations and measurements for the proposed antenna are presented to verify the design concepts featuring a very satisfactory performance. Total efficiency simulations and measurements are also presented to highlight the filtering performance of the reconfigured antenna. When the antenna was reconfigured from the UWB to work into multiple frequency bands, the radiation patterns were still the same and the total peak gain has slightly improved compared to the UWB case. In addition, when the antenna operated in the notched mode, the gain has significantly dropped at the notch frequency. The simplicity and flexibility of the proposed multimode antenna make it a good candidate for future cognitive radio front ends.


2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Chien-Jen Wang ◽  
Dai-Heng Hsieh

A small dual-band monopole antenna with coplanar waveguide (CPW) feeding structure is presented in this paper. The antenna is composed of a meandered monopole, an extended conductor tail, and an asymmetrical ground plane. Tuning geometrical structure of the ground plane excites an additional resonant frequency band and thus enhances the impedance bandwidth of the meandered monopole antenna. Unlike the conventional monopole antenna, the new resonant mode is excited by a slot trace of the CPW transmission line. The radiation performance of the slot mode is as similar as that of the monopole. The parametrical effect of the size of the one-side ground plane on impedance matching condition has been derived by the simulation. The measured impedance bandwidths, which are defined by the reflection coefficient of −6 dB, are 186 MHz (863–1049 MHz, 19.4%) at the lower resonant band and 1320 MHz (1490–2810 MHz, 61.3%) at the upper band. From the results of the reflection coefficients of the proposed monopole antenna, the operated bandwidths of the commercial wireless communication systems, such as GSM 900, DCS, IMT-2000, UMTS, WLAN, LTE 2300, and LTE 2500, are covered for uses.


A wideband coplanar waveguide (CPW) antenna with circular polarization characteristics using modified ground slot is studied in this work. Proposed design incorporates a hexagonal slot instead of rectangular slot, accounting for enhanced impedance matching. This ground slot is energized by a 50Ω feed line, resulting in excitation of two orthogonal phase quadrature modes (even-odd modes). Thus, fulfilling the essential criteria required for realizing circular polarization. A narrow horizontal slit (lg) is embedded in the ground plane at immediate left of feed line, accounting for wideband characteristics. 10dB impedance bandwidth of proposed antenna extends from 2.65- 5.60 GHz, while 3dB axial ratio bandwidth extends from 3.90- 5.80 GHz. Hence, overlapping bandwidth of proposed antenna extends from 3.90 - 5.60 GHz. RHCP characteristics with monopole radiation pattern makes proposed antenna useful for WLAN, radio navigation and radiolocation applications.


2021 ◽  
Author(s):  
Saida Ibnyaich ◽  
Samira Chabaa ◽  
Layla wakrim ◽  
Abdessalam El Yassini ◽  
Abdelouhab Zeroual ◽  
...  

Abstract A new compact pentagonal microstrip patch antenna with slotted ground plane structure, developed for use in ultrawideband applications, is studied in this article. The proposed antenna is mainly constituted by a pentagonal shaped patch antenna, a defected ground plane structure, two stubs, and four slots to improve the bandwidth. The designed antenna has an overall dimension of 30×17.59×1.6mm 3 , for WIMAX /WLAN/ WiFi/HIPERLAN-2 /Bluetooth /LTE /5G applications with a very large bandwidth starting from 2.66 GHz to 10.82 GHz (S 11 <-6 dB ). A parametric study of the ground plane structure was carried out to find the final and the optimal UWB antenna, and to confirm that the antenna has good performance and broader bandwidth. The proposed antenna prototype has been fabricated. The measured results indicate that the antenna has a good impedance matching. The antenna has an electrically small dimension with a good gain, a notable efficiency, and a wide impedance bandwidth, which makes this antenna an excellent candidate for ultrawideband wireless communication, microwave imaging, radar applications, and the major part of the mobile phone frequencies as well.


Sign in / Sign up

Export Citation Format

Share Document