Coplanar Waveguide Fed Printed Antenna with Compact Size for Broadband Wireless Applications

A novel and simple coplanar waveguide fed compact antenna is introduced in this paper. The antenna structure combines the advantages of CPW with those of the broadband antenna and simplifies the structure of the antenna by reducing the number of metallization level to construct uni-planar antenna. Prototype of the proposed antenna have been constructed and studied experimentally. The measured results agrees well with the simulated prediction and shows a broad bandwidth of 6 GHz ranging from 3.5 GHz to 9.5 GHz with VSWR ≤2 (return loss ≤−10 dB), which is equivalent to 92.3% impedance bandwidth centered at 6.5 GHz. The proposed antenna shows stable radiation characteristics, gain and axial ratio of less than 1 dB over the whole operating bandwidth. Furthermore, an extensive parametric study was performed to realize the relationship between the resonance frequencies of the broadband antennas and different parameters which is helpful for advancement of the antenna design.     

A Compact Plus Shaped Carpet Fractal Antenna with an I-Shaped DGS for C-band/X-band/UWB/WIBAN applications

This article presents the design and development of a compact broadband “+” shaped aperture coupled carpet fractal antenna with a defected ground structure (I shaped slot in the ground) for broadband/ultra wideband (UWB) and a multiband characteristics. The antenna has overall dimensions of 8.4 cm?×?5.5 cm?×?3.2 mm and is fed using aperture coupled feeding mechanism. It shows an impedance bandwidth (<?10 dB) of 4460 MHz from 6.93 to 11.39 GHz with fractional bandwidth of 0.48 at the center resonant frequency of 9.16 GHz. A multiband behavior is also exhibited by this antenna from 3.9–4.08 GHz, 4.8–5.06 GHz and 6.1–6.4 GHz with impedance bandwidths of 180 MHz, 260 MHz and 300 MHz respectively. It therefore supports the wireless applications of Wi-MAX (3.8–4.1 GHz), Wi-BAN/long distance radio telecommunication (4.8–5.06 GHz), wireless sensor networks (6.1–6.4 GHz), satellite (7.4–7.8 GHz) and UWB (6.9–11.03 GHz). The antenna is designed as a ‘+’ shaped patch with fractal rectangular slots cut out from it up to iterations of second order that allow the antenna to support multiband characteristics. The bandwidth at these bands is improved by using I shaped defected ground structure (DGS) and a parasitic feeding method i.e. aperture coupled feeding (Karur et al., in: ICMARS (IEEE), Jodhpur, India, pp. 266–270, 2014).The antenna has a compact structure with two layers of FR4 substrate, the ‘+’ shaped carpet fractal printed on the upper substrate layer and the lower substrate has a ground layer printed on its top and feed line on its bottom layer respectively. It shows a simulated peak gain of 4 dB at an operation frequency of 7.95 GHz. The antenna design and simulations are done using CST MWS V14. The Simulation results in terms of impedance bandwidth, smith chart, gain are presented in this article. To validate the impedance bandwidth results, the proposed carpet fractal antenna is experimentally tested using a vector network analyzer and the measured results are found to be closely matching with the simulated ones, allowing the antenna to be practically suitable for the afore mentioned wireless applications.

     

3.5/5.5 Ghz dual band-notch ultra-wideband antenna

A compact and simple design of a CPW-fed planar antenna for ultra- wideband application with dual band-notch characteristics is presented. The proposed antenna yields an impedance bandwidth of 3.1- 10.6 GHz with VSWR < 2, except the bandwidths of 3.3-3.9 GHz for WiMAX and 5-6 GHz for WLAN. The antenna is successfully simulated, designed, and measured, showing broadband matched impedance, stable gain and omnidirectional radiation patterns.     

Design of a Compact Hexagonal Monopole Antenna for Ultra—Wideband Applications

This paper presents two design compact hexagonal monopole antennas for ultra-wideband applications. The two antennas are fed by a single microstrip line . The Zeland IE3D version 12 is employed for analysis at the frequency band of 4 to 14 GHz which has approved as a commercial UWB band. The experimental and simulation results exhibit good agreement together for antenna 1. The proposed antenna1 is able to achieve an impedance bandwidth about 111%. The proposed antenna2 is able to achieve an impedance bandwidth about (31.58%) for lower frequency and (62.54%) for upper frequency bandwidth. A simulated frequency notched band ranging from 6.05 GHz to 7.33 GHz and a measured frequency notched band ranging from 6.22 GHz to 8.99 GHz are achieved and gives one narrow band of axial ratio (1.43%). The proposed antennas can be used in wireless ultra-wideband (UWB) communications.     

Design of Printed Monopole Antennas on Liquid Crystal Polymer Substrates

In this paper, a compact printed monopole antenna with an extremely wide bandwidth has been realized on Liquid Crystal Polymer (LCP) substrates by using standard processing technology. Both laminated and directed metalized LCP substrates were used in this experiment. The antenna made on the direct metalized LCP substrate performed well compared to on the laminated LCP substrate. To improve the adhesion, the surface of the LCP was further roughened and a certain adhesion layer was used prior to the deposition of Cu. The measured antenna on a metalized LCP substrate could cover this frequency band with an impedance bandwidth from 0.51 GHz to 14.4 GHz (28.2:1) for VSWR≤2. Moreover, the antenna exhibits a nearly omni-directional radiation pattern. The size of this antenna is only about 0.18λ₁ × 0.13λ₁, where λ₁ is the wavelength of the lowest operating frequency. The results show that LCP is a promising candidate for high frequency applications.     

Printed Planar Monopole Antenna Design for Ultra-Wideband Communications

This paper presents an ultra wideband (UWB) planar printed monopole antenna fed by microstrip line. The antenna configuration contains a beveled ground plane. The beveled partial ground plane improves the impedance bandwidth. The measured frequency response demonstrates that the fabricated antenna exhibits an impedance bandwidth of 7.9 GHz over 3.1 to 11 GHz for VSWR < 2. The proposed antenna has ultra-wideband characteristics with omnidirectional radiation pattern and stable gain. Ultra-wideband performance of the proposed antenna is examined through the simulated surface current distributions. Measured results confirm that the antenna is suitable for UWB applications due to its compact size and high performance characteristics.     

A Compact CPW-Fed Planar Stacked Circle Patch Antenna for Wideband Applications

The article investigates the performance of planar and compact CPW-fed microstrip patch antenna that offers 10 dB impedance bandwidth over the wide frequency range between 2.59 and 7.61 GHz. The parametric analysis of various design variables is included to acquire the final design of proposed antenna. The prototype exemplary of designed antenna is experimentally tested to obtain the return loss, VSWR, radiation response and gain characteristics. The close agreement is acquired between simulated and experimental results.The projected antenna has compact size of 0.61λ₀ × 0.44λ₀ × 0.027λ₀ mm³ and offers a 10 dB wide impedance bandwidth of 5.02 GHz. Thus, it may be considered suitable for variety of wireless applications including WLAN, Wi-MAX, fixed satellite services, wireless point-to-point applications etc.

     

Ultra-Wideband and Uni-Directional Radiation Slot Antenna for Multi-Band Wireless Communication Applications

In this paper, a ultra-wideband slot antenna is proposed and developed for multi-band wireless communication applications. The radiating slot is fed by a microstrip line with a microstrip fork shaped tuning stub and backed by a finite metallic reflector. The frequency characteristic and radiation performance of the proposed antenna are successfully optimized and the related prototypes are fabricated and tested. The measured results show that the impedance bandwidth can cover the band from 1.85 to 6.1 GHz with return loss of better than 10 dB. The obtained patterns display a high gain and uni-directional radiation patterns within interested bands. With these features, the proposed structure is suitable for application in wireless communication systems, where a single antenna is needed to operate at multi-bands simultaneously, such as PCS (1.85–1.99 GHz), UMTS (1.92–2.17 GHz) and all WLAN bands (2.4–2.48 GHz, and IEEE802.11a WLAN applications: 5.15–5.35 and 5.725–5.825 GHz).     

Compact printed ultra-wideband monopole antenna with dual band-notch characteristic

A compact ultra-wideband microstrip-fed planar antenna with dual band-notch characteristic is presented. Two notched frequency bands are achieved by embedding an E-slot in the radiation patch and a U-slot defected ground structure in the feeding line. Moreover, the two notched bands can be controlled by adjusting the length of the corresponding slot. Experimental results show that the proposed antenna, with compact size of 35 x 14 mm, has an impedance bandwidth of 2.87-10.91 GHz for a voltage standing-wave ratio less than 2, except two frequency notched bands of 3.49-4.12 and 5.66-6.43 GHz.     

Compact ultra-wideband antenna with tri-band notched characteristic

A compact ultra-wideband printed planar antenna with tri-band notched characteristic is presented. Two different types of slots are used to obtain tri-band notched characteristic. By using a U-slot defected ground structure, a notched band, 5?6 GHz for WLAN, is achieved. An H-shaped slot is etched on the radiating patch to obtain another two notched bands at 3.3?3.7 GHz for WiMAX and 7.2 GHz for some C-band satellite communication systems. The proposed antenna yields an impedance bandwidth of 3.1?10.6 GHz with VSWR , 2, except the notched bands. The antenna is successfully simulated and measured, showing tri-band notched characteristic can be obtained by using two different slots.     

Concurrent 60/94 GHz SIR Based Planar Antenna for 5G/MM-Wave Imaging Applications

The present research work aims towards the design of a stepped impedance resonator (SIR) based dual band antenna having resonant frequencies at millimeter wave: V band (center frequency: 60 GHz) and W band (center frequency: 94 GHz). The structure comprises of stepped impedance resonator (SIR) patch, two stepped section impedance matching network and a microstrip feedline. The fractional bandwidth of the proposed dual band antenna is 2.9 GHz (4.8%) and 6.25 GHz (6.6%) at 60 and 94 GHz, respectively. The far field polar plots show broadside radiation pattern having gain of 7.9 dBi at 60 GHz and 4.2 dBi at 94 GHz. Further, as a testimony of this concept, scaling principle was used and accordingly microwave scaled antenna was devised. The prototype scaled hardware results matched closely with the designed mm-wave antenna. Further, the proposed dual frequency antenna finds enormous applications towards development of pioneering millimeter wave systems like; 60 GHz is focused on multi gigabit WPAN communication and 94 GHz frequency is currently extensively used for millimeter wave imaging applications. The proposed design is very simple, conformal and easily extendable as an array for MMIC applications for compact frontend design.

     

A Compact Semi-circular Slot MIMO Antenna with Enhanced Isolation for Sub-6 GHz 5G WLAN Applications

In this paper, a novel compact semi-circular slot (SCS) 2 × 2 MIMO antenna is presented for 5G NR sub-6 GHz applications with high isolation. The proposed antenna consists of a semi-circular slot in ground plane, U-shaped stub, and 50-ohm microstrip feed line. The novelty of this paper are the Semi-Circular Slot acts a radiator, the port isolation  is enhanced using a simple conductor strip as a neutralization line, very compact in size, low ECC, and good impedance matching. The overall size of the proposed SCS MIMO antenna is 16 mm x 21 mm, and FR4 substrate is used with thickness of 1.6 mm. The two SCS antenna elements are separated by edge-to-edge distance of 1mm (\(=0.019\lambda _{0}\)). The proposed compact MIMO antenna design is simulated using Ansys HFSS. To validate SCS MIMO antenna, a prototype was fabricated and tested. The measured results are attained at 5.5 GHz with isolation greater than 25dB, impedance bandwidth (S11\(<-10\) dB) covers from 5.10 GHz to 5.80 GHz with return loss of ? 39.5 dB. The MIMO antenna parameters, ECC, CCL, TARC, and MEG are studied, and the values are obtained within acceptable limits. The measured and simulated antenna results are almost similar. This compact MIMO antenna is suitable for 5G communications in sub-6 GHz wifi-5 band applications.

     

Compact Chip-Resistor Loaded Active Integrated Patch Antenna for ISM Band Applications

As technology is moving towards miniature structures, demand for designing efficient compact antennas is increasing simultaneously. So it would be valuable to improve the features of small antennas, such as bandwidth and gain. A compact chip-resistor loaded microstrip antenna at 2.48 GHz frequency for industrial scientific and medical (ISM) band, with dimensions of 10 × 10 mm² is presented in this paper. With a novel geometry design, antenna is promoted to an active integrated antenna (AIA) on a two-layer printed circuit board (PCB), which contains passive antenna and active circuitry with a common ground plane. A monolithic amplifier is used to have an improvement around 10 dB in antenna gain. The impedance bandwidth has been increased during chip-resistor loading and adding active circuitry processes. For chip-resistor loaded antenna, that is 5.7 and 9.48% in simulation and measurement respectively. Moreover, the active integrated antenna has the measured impedance bandwidth of 58.7%. Since the low gain and narrow bandwidth of compact microstrip antennas might be a challenge for their operation, by compensating these drawbacks, proposed antenna would become more practical for special medical diagnostic applications, where doctors need stronger signals for monitoring.

     

Compact UWB monopole antenna with quadruple band notched characteristics

ABSTRACT

A compact planar Ultrawideband (UWB) monopole antenna with quadruple band notch characteristics is proposed. The proposed antenna consists of a notched rectangular radiating patch with a 50 Ω microstrip feed line, and a defected ground plane. The quadruple band notched functions are achieved by utilising two inverted U-shaped slots, a symmetrical split ring resonator pair (SSRRP) and a via hole. The fabricated antenna has a compact size of 24 mm × 30 mm × 1.6 mm with an impedance bandwidth ranging from 2.86 to 12.2 GHz for magnitude of S₁₁ < ?10 dB. The four band notched characteristics of proposed antenna are in the WiMAX (worldwide interoperability for microwave access) band (3.25–3.55 GHz), C band (3.7–4.2 GHz), WLAN (wireless local area network) band (5.2–5.9 GHz) and the downlink frequency band of X band (7–7.8 GHz) for satellite communication are obtained. The measured and simulation results of proposed antenna are in good agreement to achieve impedance matching, stable radiation patterns, constant gain and group delay over the operating bandwidth.     

A Pentagonal Shaped Microstrip Planar Antenna with Defected Ground Structure for Ultrawideband Applications

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?×?1.6 mm³, for WIMAX/WLAN/WiFi/HIPERLAN-2 /Bluetooth/LTE/5G applications with a very large bandwidth starting from 2.66 to 10.82 GHz (S₁₁?<???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.

     

Fractal based ultra-wideband antenna development for wireless personal area communication applications

This paper presents a bandwidth enhanced, compact planar ultra-wideband antenna design for wireless personal area communication (WPAN) applications. The proposed antenna has fractal based geometry and is constructed using several iterations of a pentagon slot inside a circular metallic structure. The partial ground plane of the basic radiator is tapered, defected and a U slit is etched out from the microstrip feed to improve the −10 dB |S11| bandwidth. The proposed fractal based antenna has an impedance bandwidth from 2.9 GHz to 15 GHz with low profile configuration and is fabricated on FR4 substrate with dimensions of 32 mm × 32 mm × 1.6 mm. To authenticate the designed prototype, the antenna is fabricated and tested for impedance and radiation characteristics. The designed antenna has stable radiation characteristics in the operating band. Furthermore, the antenna is validated for its applicability in WPAN, by calculating fidelity factor through time domain analysis along with the transmission coefficient and group delay measurements.     

Ultrawide-band square planar metal-plate monopole antenna with a trident-shaped feeding strip

A square planar metal-plate monopole antenna fed by using a novel trident-shaped feeding strip is presented. With the use of the proposed feeding strip, the square planar monopole antenna studied shows a very wide impedance bandwidth of about 10 GHz (about 1.4-11.4 GHz, bandwidth ratio about 1:8.3), which is larger than three times the bandwidth obtained using a simple feeding strip (about 1.5-3.3 GHz, bandwidth ratio about 1:2.3). In addition, the proposed feeding strip can be integrated with the square planar monopole, that is, the feeding strip and the square planar monopole together can be easily fabricated using a single metal plate, making the proposed antenna easy to construct at a low cost. Details of the experimental and simulation results for the proposed planar monopole antenna are presented and analyzed.     

Bandwidth enhancement of a printed wide-slot antenna with small slots

In this paper, four printed wide-slot antenna fed by a microstrip line with a polygonal slot for bandwidth enhancement is proposed and experimentally studied. One of these antennas is fabricated and measured. Impedance, radiation and gaincharacteristics of this antenna are presented and discussed. From experimental results, the measured impedance bandwidth, defined by 10-dB return loss, can reach an operating bandwidth of 4.03 GHz at operating frequencies from approximately 1.87 to 5.90 GHz.     

梯形接地板结构超宽带天线设计

在圆形单极天线的基础上进行改进设计了一款梯形接地板结构的超宽带单极天线。根据接地板电流的分布强弱,削去矩形接地板两端对电流影响较小的三角形形状部分,构成梯形接地板。经过仿真优化实验结果表明,该天线电压驻波比VSWR2的阻抗带宽为3.1~17 GHz,工作频段内具有全向辐射特性,且天线只有20 mm×22 mm×1.6 mm,结构简单,适合超宽带无线通信系统的要求。     

Compact ultra-wideband antenna with dual bandstop characteristic

A simple and compact ultra-wideband microstrip-fed planar antenna with dual bandstop characteristic is presented. By using a U-slot defected ground structure (DGS) in the feedline, a stopband of 600 MHz (from 5.45 to 6.05 GHz) for band rejection of WLAN is achieved. To obtain another stopband, an arched slot is etched on the radiating patch. Experimental results show that the designed antenna, with a compact size of 30 times 24.5 mm, has an impedance bandwidth of 2.8-11 GHz for voltage standing wave ratio (VSWR) less than 2, except two frequency stop-bands of 3.5-4.25 GHz and 5.45- 6.05 GHz. Moreover, the antenna has good omnidirectional radiation patterns in the H-plane.