CPW-fed Ultra-wideband Antenna Research Articles

Systematic Analysis of Rotated Dual-Split Elliptical SRR with Band-Stop Characteristics

In this research article, a novel double-split elliptical split ring resonator (DS-ESRR) is proposed to achieve frequency-notching behavior of ultrawideband filtenna, where the semimajor and minor axes of the ellipse are taken as a bivariate random variable and expressed in Ramanujan’s correction coefficient so that more degree of freedom is available for choosing degenerated impedance and thus for variable frequency-notching applications. To verify this hypothetical method, finite sets of variables for DS-ESRR are presented in this proposed work, and a mathematical expression is formulated to estimate the resonant frequency of the DS-ESRR, such that for practical applications, frequency-notching parameters can be easily estimated accurately rather than previously used SRR like circular or square-shaped geometry. DS-ESRR is deployed at the back of a CPW-fed ultrawideband antenna for notching filter application, and the computed data is compared with the eigen mode simulation results which reveal good agreement with each other.

An ultrawideband antenna with two independently tunable notch bands

This paper presents a planar CPW-fed Ultrawideband (UWB) antenna with two independently tunable notch bands. The proposed design consists of a modified Rhombus-shaped monopole structure that is integrated with a dual band-stop filter based on hexagonal split ring resonators (HSRR). The antenna is capable of suppressing multiple frequency bands within ultrawideband range (3.1–11 GHz) such as WLAN and X-band downlink satellite communication frequency bands with an independent tunable mechanism to fulfill the on-demand band rejection. The frequency reconfigurability of the two notch bands is obtained by loading the hexagonal filter arms with two varactor diodes (for each band). Details of antenna design steps and reconfigurability mechanism are illustrated. The notch band element is explained using equivalent circuit model and surface current distribution at lower and higher notch frequency bands. A prototype of the proposed design is printed on the RO4003C (ϵr = 3.55) substrate printed circuit board (PCB) and tested to authenticate the performance. The proposed antenna volume is 21.5 ▪ 48 ▪ 1.524 mm3 and demonstrates an omnidirectional radiation pattern in E and H planes with an average gain of 3.7 dBi across the operational passbands, while a sharp reduction in gain of -6.8 dBi and -3.5 dBi is achieved at the lower and higher notch bands, respectively. Continuous tuning is achieved experimentally from 5.08 to 5.77 GHz and 7.75 to 8.52 GHz for the lower and higher notch bands, respectively. Excellent agreement is observed between the simulated and measured results. Application areas include radio-frequency identifications, ground-penetrating radar, and wireless communications.

Design of Dual-Band Notched UWB Antenna Loaded with Split Ring Resonators for Wide Band Rejection

ABSTRACT Nowadays, the design of a miniaturised ultra-wideband (UWB) antenna with wide dual band-notched characteristics gained widespread demand in wireless communications to reduce interference. The design of a planar CPW-fed circular UWB antenna loaded with split ring resonators and stubs is presented to eliminate two frequency bands. Two symmetrical circular split ring resonators are etched below the CPW feed at the backside of a circular UWB monopole antenna to suppress 3.61 GHz–5.57 GHz (sub-6 GHz band) wideband interference, whereas the 7.06 GHz–8.79 GHz (X-band uplinks and downlinks) band is suppressed by loading two L-shaped stubs. Slots are also made on the patch and ground to enhance impedance matching at a lower resonance frequency. The proposed notch band antenna has a compact size of 38 × 32 × 1.6 mm3 and has the highest gain of 5.75 dB at a frequency of 9 GHz. The parametric analysis has been performed to obtain optimised dimensions for better performance. The designed antenna is simulated, prototyped and tested to validate the antenna design.

A Compact CPW-Fed UWB Antenna with Dual-Band Notched Characteristics for WiMAX/WLAN Applications

A dual-notched bands ultra-wideband (UWB) antenna with coplanar waveguide (CPW) fed is presented in the paper. The two notched bands are selected at 3.5 and 5.8 GHz frequencies to overcome the interference from WiMAX and WLAN bands. The overall size of the antenna is 17.5×17.5 mm2, which can be considered as one of the smallest UWB antennas in the literature. The developed antenna has an impedance band width ranging from 2.9 to 13 GHz. The measured radiation patterns on E and H planes are nearly omni-directional and stable with acceptable gain over the entire band. The dual-band notched at WiMAX and WLAN is created by embedding I-shaped and C-shaped stubs in the radiation patch of the antenna. Due to the compactness, good radiation patterns and the reasonable stable gain, this antenna is well suited for integration into portable wireless communications devices for UWB applications.

Gain enhancement of a quad notched CPW fed UWB antenna

AbstractIn this article, a compact quad notched CPW fed ultrawideband (UWB) antenna of the size 35.4 × 26.6 × 1.6 mm3 with improved gain characteristic is proposed. The designed antenna has bandwidth ranging from 2.85 GHz to 11.45 GHz with the notching capability at WiMAX, C‐band, WLAN and downlink of X‐band for satellite communication. The gain of the antenna is improved by using two antennas in the stacked configuration without raising the overall size of the antenna in horizontal plane and maintaining the impedance matching over the ultrawideband range. The prototype of the proposed antenna has been fabricated on FR4 substrate and its performance parameters are measured and compared with the simulated results, which are in good agreement. The simulated and measured result shows the improvement of antenna peak gain by 4.2 dBi and thus improving the peak gain by 162%. The proposed antenna is an excellent candidate for the high gain UWB portable communication devices in the environment having different narrow interfering bands of WiMAX, C‐band, WLAN, and downlink X‐band of satellite communication.

Novel CPW-fed UWB antenna for X-band applications

A very compact coplanar waveguide (CPW)-fed ultra-wide band (UWB) printed antenna (PMA) is presented. The proposed antenna is supposed to cover the UWB range from 7 GHz to 10 GHz, with return loss values below −10 dB in the whole frequency range, for X-band applications, often used for dense satellite communications. The 30 $\pmb{\mathrm{x} 35 \mathrm{x} 1.6 \mathrm{mm}^{3}}$ antenna is mounted on a dielectric substrate named FR-4 with thickness $\pmb{\mathrm{h}=1.6}\mathbf{mm}$ , relative permittivity $\varepsilon \mathrm{r}=4.3$ and loss tangent of 0.025. All the design and simulated results are performed using CST Microwave Studio, 3D Electromagnetic Simulator software. The results show broad bandwidth and good omnidirectional radiation patterns in the passband, with a very compact size. The satisfactory overall performance with such a simple structure and small size makes the proposed antenna attractive for use in ultra-wide band (UWB) systems, especially for X-band applications.

A CPW-fed flexible UWB antenna for IoT applications

In order to keep pace with the growing research and development on flexible and reconfigurable electronics, this research presents an inkjet printed ultra-wideband (UWB) flexible antenna on photo paper. The antenna pattern comprises a circular patch with the double stepped symmetric ground plane and is fed by a coplanar waveguide (CPW) technique on one-sided photo paper. The system is designed, simulated, fabricated, and tested experimentally. It operates over 3.2–30 GHz (161% fractional bandwidth, FBW) range with a return loss of − 10 dB or less and a voltage standing wave ratio (VSWR) < 2. The proposed monopole antenna is of dimensions 33.1 mm × 32.7 mm × 0.254 mm with an electrical size of 0.35 λ × 0.35 λ at 3.2 GHz frequency. This design exhibits nearly omnidirectional radiation pattern over the entire impedance bandwidth. An average gain of 4.87 and a radiation efficiency of 86.61% was observed. The miniature size, higher operating range, relatively constant radiation pattern along with higher acceptable peak gain of the antenna on a paper substrate lend itself to wearable and Internet of Things (IoT) applications.

Novel SRR-loaded CPW-fed UWB antenna with wide band-notched characteristics

This paper presents the design of a split-ring resonators (SRR) loaded coplanar waveguide-fed ultra-wide band (UWB) antenna. As using the electromagnetic coupling SRR connected by open-ended microstrip lines, this UWB antenna achieves wide band-notched characteristics. The frequency of the proposed antenna operates from 2.37 to 10.93 GHz with a broad notch band covers from 4.96 to 6.15 GHz (IEEE 802.11.ac), the relative stopped bandwidth of the notch band achieves 20.42%. Besides, theoretical analysis and experimental results are proposed to illustrate and validate this proposed antenna.

CPW Fed UWB Antenna by EBGs With Wide Rectangular Notched-Band

Ultra-wideband (UWB) antennas with wide rectangular notched-band are proposed in this paper. The rectangular notched-band design is realized by placing dual mushroom-type electromagnetic-bandgap (EBG) structures on the CPW feeding line. The patches of the EBGs are laid on the back size of the substrate and dead against the CPW feeding line. Shorting pins are utilized to connect the patch and the feeding line. Then, the CPW feeding line operates as ground plane for the EBGs. By tuning the two resonant frequencies of the EBG structures and making them merge with each other, a rectangular notchedband is achieved. Research also found that design methodology has the ability to tune the width and the frequency of the rectangular notched-band by adjusting the EBG parameters. Then, three cases of rectangular notchedband designs to reject the wireless local-area network (WLAN, 5.150-5.825 GHz) interference band and the X -band downlink satellite communication band (660 MHz, 7.10-7.76 GHz) were designed by using different EBG parameters. The design methodology can also be utilized to design rectangular notchedband for other interference bands efficiently.

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

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.

Design of CPW-fed asymmetric slot UWB antenna for wireless application

A compact Ultra-WideBand (UWB) slot antenna is presented in this paper. The slot is modified rectangular in shape and asymmetrically cut in the ground plane. A hexagonal patch with two stepped CoPlanar Waveguide (CPW) feed is used to excite the slot. Wider impedance bandwidth is achieved due to the extra inductive reactance created by the asymmetric slot which neutralizes the capacitive reactance of the hexagonal patch. 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 obtained and found to be omni-directional in H-plane and bi-directional in E-plane.

CPW-fed compact thin-film UWB antenna with dual band-notched characteristics

This paper presents a new compact thin-film ultrawideband (UWB) antenna with dual band-notched characteristics. The antenna contains a rectangular slot with a fork-like tuning stub. To achieve the dual band-notched characteristics, narrow and U-shaped slots are inserted on the radiator. This antenna is printed on a Mylar film substrate of 0.3 mm thickness with a dielectric constant of 3.2. The antenna has compact dimensions of 34.5 × 27.3 mm2. It operates in the frequency range 2.9–11.3 GHz with impedance matching covering the entire bandwidth and reasonable radiation properties. It also exhibits dual band-notched characteristics. One of the notched frequencies is in the range 3.3–3.7 GHz (WiMAX band) and the other in the range 5.1–5.8 GHz (WLAN band). The antenna is designed and simulated by using the commercial IE3D software, which is based on the method of moments. The antenna was fabricated and measured using Agilent E363B PNA network analyzers. The characteristics of the fabricated antenna show high correlation with those obtained from the simulation. The results confirm that the proposed antenna can achieve notch performance for WLAN and WiMAX communication systems and is also suitable for various portable UWB applications. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Circular Patch Antenna with C-shape Slot for UWB Application

A novel compact and ultrawide-band (UWB) antenna is presented in this paper. A novel CPW-fed monopole circular patch UWB antenna with c-shape slot is proposed in this article. IE3D simulator is used to analyze the proposed antenna in the design process. The proposed antenna has an extremely wide frequency band range, the impedance bandwidth of which is measured as 4.2 to 10.5 GHz for return loss <_10 dB. Simulated and measured results are presented for the proposed antenna.

A CPW-fed circular slot UWB antenna with WLAN band and X-band filtering characteristics using hybrid resonators

A compact coplanar waveguide (CPW)-fed circular slot ultrawideband (UWB) antenna with dual-band filtering characteristic is presented in this article. The dual-band filtering characteristic is achieved by inserting an arc-rectangle-shaped stepped impedance resonator in the circular ring radiation patch and etching a spiral stepped impedance resonator in the CPW-fed transmission line. The numerical and experimental results demonstrate that the proposed antenna can operate on a frequency band between 2.7 and 12 GHz with voltage standing wave ratio less than 2, except for that two filtering bands between 4.8 and 6 GHz and between 7.6 and 8.6 GHz are used to prevent the potential interference from WLAN band and X-band. In addition, the proposed antenna has a compact size and omnidirectional radiation pattern, which is suitable for UWB communication applications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:925–929, 2014

A Novel CPW-Fed UWB Antenna with Band-Stop Function

A novel coplanar waveguide-fed (CPW) ultrawideband (UWB) antenna with band-stop function is presented in this paper. The proposed antenna comprises a CPW-fed slot rectangular patch with an open stub ground plane, and two inverted L-shaped strip conductors are fabricated on the back plane. The overall size of the antenna is 25 × 25 × 1.6 mm2, and it achieves good impedance matching and radiation gain. Simulated and measured results show that the designed antenna operates at 2.9 GHz–13.08 GHz with band rejection in the frequency band of 7.7 GHz–9.05 GHz for satellite applications, and the proposed antenna is suitable for UWB wireless communication applications.

Design and Simulation of Rectangular Slotted Patch Antenna with Air Gap

A compact and ultra-wideband CPW-fed antenna with wide band frequency characteristic has been proposed, and the simulation results are discussed. Due to its electrical characteristics such as very small volume, wide impedance bandwidth, WiMAX band rejection, omnidirectional radiation pattern, and small group delay, the proposed antenna is expected to be a good candidate in various UWB systems.The bandwidth of the proposed antenna to be 2.7 GHz and a center frequency of 2.6GHz is obtained with return loss of -18.58dB. VSWR is less the 2 in the range of frequency 1.8 to 4.6 GHz. The proposed antenna is sutable for hend held device, WIMAX, mobile communication, and wireless applications.

Single-Layer Differential CPW-Fed Notch-Band Tapered-Slot UWB Antenna

A single-layer differential coplanar waveguide (CPW)-fed notch-band tapered-slot ultrawideband (UWB) antenna is proposed in this letter. In order to achieve the sharp and controllable notch-band characteristic, one pair of half-wavelength stubs and slits are introduced inside the tapered slot and in the circular patches, respectively. Compared to a single-ended CPW-fed UWB antenna, due to adopting the differential feeding structure, the proposed antenna has lower cross polarization. Since all of the structures are printed on the same layer of the substrate, it can be fabricated easily and very suitable to be integrated with RF front-end circuits. The measured -10-dB impedance bandwidth is 126% (from 2.78 to 12.3 GHz), along with a sharp notch band from 5.2 to 6.0 GHz. Good agreement is achieved between the measured results and simulated results.

CPW-FED UWB antenna with band-stop properties

Structurally simple and miniaturized ultra wideband (UWB) printed rectangular antenna fed by a coplanar waveguide (CPW) is proposed.Overall dimension of the antenna is as compact as 12 (0.13λ) × 12 (0.13λ) × 1.6 mm3, where λ is the wavelength of the first resonance of the antenna. The main feature of the proposed antenna is its compact size and controllable structure which lead to four different antenna designs. By adjusting the dimensions of the elements of the antenna, notch frequency in different ranges of the UWB can be obtained. The resulting VSWR < 1.5 impedance bandwidth is as large as 11.6 GHz. The antenna presents a stable gain and omnidirectional radiation pattern in its operational frequencies. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1533–1537, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27624

A compact CPW-FED UWB antenna with independent dual band-notched characteristics

In this article, a new design of a coplanar waveguide fed (CPW-fed) ultra-wideband (UWB) antenna with dual band-notched characteristics is presented. To achieve ultra-wideband impedance matching, the tapered geometry is adopted. The two meandered split resonant slots that are etched on this antenna are to reduce the possible interferences with the band of 3.2–3.8 GHz and 5.1–5.8 GHz, which cover both WLAN and WiMAX. The upper slot (shorter in length) controls the higher band, while the lower one (longer in length) controls the lower band. Antennas with and without slots are analyzed and compared, which indicates the ability of two incorporated slots to tune the notch-band independently. A prototype is fabricated and measured, and the good agreement between simulated and measured results manifests the effectiveness of this design. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1126–1130, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27519

Dual-band notched ultra-wideband antenna by using step-by-step design inside conductor-backed plane

A coplanar waveguide fed (CPW-fed) ultra-wideband antenna with dual band-notched characteristics is proposed. The main features of the proposed antenna are the compact dimensions and band-notched characteristics that are achieved without modifying the radiator or the CPW-ground plane. Dual band-notched characteristics are achieved by M-shaped strip inside the slotted conductor-backed plane. Also, wider impedance bandwidth can be achieved with this structure. The measured results show that the proposed antenna operates over the frequency band between 2.6 GHz and 11.7 GHz (127%), defined by VSWR < 2, except two notched bands (3.25–4.32 GHz and 5.02–5.97 GHz), where the VSWR is more than eight, aimed at suppressing any interference from IEEE802.16 WiMAX (3.3–3.6 GHz), C-band (3.7–4.2 GHz), and IEEE802.11a WLAN (5.15–5.825 GHz). The designed antenna has a small size of 15 × 15 mm2. The antenna has a desirable VSWR level, radiation pattern and gain characteristics for ultra-wideband frequency band range. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1069–1074, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27512