Compact Folded Monopole Antenna Excited by a Conductor‐Backed Coplanar Waveguide with Vias

A compact monopole antenna excited by a conductor‐backed coplanar waveguide (CBCPW) is developed for wireless USB dongle applications. The proposed antenna has a compact dimension of 14 mm × 47.4 mm × 3.5 mm, which is suitable for a USB dongle housing. A slotted elliptical patch and a CBCPW with vertical vias are employed to achieve a further size reduction and an improved impedance bandwidth. The measurement result demonstrates that the fabricated antenna resonates from 2.25 GHz to 10.9 GHz, which covers all of the important wireless communication bands, including WiBro (2.3 GHz to 2.4 GHz), Bluetooth (2.4 GHz to 2.484 GHz), WiMAX (2.5 GHz to 2.7 GHz and 3.4 GHz to 3.6 GHz), satellite DMB (2.605 GHz to 2.655 GHz), 802.11b/g/a WLAN (2.4 GHz to 2.485 GHz and 5.15 GHz to 5.825 GHz), and ultra‐wideband (3.1 GHz to 10.6 GHz) services. The radiation characteristics of the proposed antenna when attached to a laptop are tested to investigate the influence of the keypad and the LCD panel of the laptop.     

Compact Circularly Polarized Antenna with a Capacitive Feed for GPS/GLONASS Applications

This letter presents a novel compact circularly polarized patch antenna for Global Positioning System/Global Navigation Satellite System (GPS/GLONASS) applications. The proposed antenna is composed of a simple square radiating patch fed by a capacitive dual‐feeder to increase the impedance bandwidth and a lumped element hybrid coupler to achieve the broadband characteristic of the axial ratio (AR). The realized antenna dimensions are 28 mm × 28 mm × 4 mm, which is the most compact size among the dual‐band GPS/GLONASS antennas reported to date. The measured results demonstrate that the proposed antenna has a gain of 2.5 dBi to 4.2 dBi and an AR of 0.41 dB to 1.51 dB over the GPS/GLONASS L1 band (1.575 GHz to 1.61 GHz).     

Design of an Internal Antenna with Near‐Omnidirectional H‐Plane Radiation Pattern over Ultra‐wide Bandwidth

In this paper, an ultra‐wideband internal antenna for use in mobile applications is proposed. The proposed antenna has symmetrical bi‐arm structures printed on the top and bottom of the substrate, and it occupies a compact area of 10 mm × 10 mm × 1 mm. The designed antenna has an impedance bandwidth from 3 GHz to 12 GHz and near omnidirectional radiation patterns over the frequency band of interest. The group delay between two antennas fabricated using the proposed design is less than 0.8 ns, and the maximum gain variation is about 3.16 dB.     

一种具有三阻带特性的超宽带天线的设计与研究*

提出了一种紧凑型共面波导馈电的具有三阻带特性的超宽带天线。所设计天线的基本几何结构由共面波导(CPW)馈电线、菱形辐射贴片和矩形宽缝隙组成。通过在辐射贴片上刻蚀一个U型槽,以及在共面波导的接地面上增加两对L型的寄生旁枝结构来实现天线的三陷波特性。天线尺寸为32mm×32mm×0.508mm。仿真和实验结果表明,该天线在2.6~11.5GHz的频段内电压驻波比小于2,在3.15~3.80GHz、5.20~5.80GHz和8.2~8.7GHz三个频段内具有陷波特性,分别有效阻隔了Wi MAX系统、WLAN系统和ITU 8GHz频段信号对于超宽带(UWB)系统的干扰。在除三个阻带频段外的其余UWB工作频段范围内,具有良好的辐射方向特性和稳定的增益。仿真结果和实验结果表现出良好的一致性。     

Multiband Multiple Elliptical Microstrip Patch Antenna with Circular Polarization

In this paper a compact low profile elliptical fractal patch antenna for high gain and multiband is presented which resembles Lorentz fractal shape. By introducing fractal on ellipse patch multiband applications are achieved. With the help of CST Microwave Studio Suite TM the proposed structure has been designed and analyzed. The simulated results are confirmed experimentally. The suggested antenna has a dimension of 40?×?55 mm² (L?×?W) and resonant frequencies obtained are 1.7, 3.2, 3.9, 5.9, 7.8, 8.6, 9.7, 11.4 and 12.6 GHz with VSWR?≤?2. The aerial is assembled on FR-4 (ε_r?=?4.4) substrate with thickness of substrate 1.6 mm. This antenna holds applications in many satellite communication transmissions, some Wi-Fi devices, cordless telephones, and weather radar systems.     

Design of a wideband Y-shaped antenna for the application in IoT and 5G communication

A small wideband Y-shaped antenna is presented in this paper. A monopole of Y-shaped with two rectangular-shape frequency shifting strip is used to produce a compact dimension of 10 mm × 12 mm on a 1-mm-thick FR4 substrate. The antenna has an impedance bandwidth (measured below ?10 dB from 39.57 to 44.63 GHz), a gain more than 4.9 dB, radiation efficiency of 81%, and voltage standing wave ratio (VSWR) < 2, within the bandwidth of interest, making it a viable option for 5G applications. The use of a (01.7850 × 2.6775 × 00.02) mm³ metallic strip located above the feed line is also shown to efficiently increase the antenna bandwidth to values greater than 5 GHz without affecting the other antenna parameters. Additionally, the measured results in comparison with the simulated results reveal negligible changes, confirming that the proposed antenna is also suitable for the applications of 5G with Internet of Things.     

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.

     

Design and realization of low profile dual-wideband monopole antenna incorporating a novel ohm (Ω) shaped DMS and semi-circular DGS for wireless applications

In this paper, a compact microstrip line fed dual-wideband printed monopole antenna (PMA) for wireless communication applications is presented. The proposed antenna consists of an asymmetric rectangular patch via a microstrip-fed line, an ohm (Ω) shaped DMS loaded at the rectangular patch, and dual semi-circular shaped DGS embedded in the partial rectangular ground plane. The combination of an ohm shaped DMS and two semi-circular DGS is used to broaden the bandwidth of the two bands and improve the return loss for the desired antenna. The measured 10 dB bandwidth for return loss are achieved to be 21.52% (3.40–4.22 GHz) and 47.32% (5–8.1 GHz) in the lower and upper band, respectively which covers the bandwidth requirements of 5.2/5.8 GHz WLAN and 3.5/5.5 GHz Wi-MAX application bands. Furthermore, the proposed antenna has a very simple planar structure and occupies a small area of only 621 mm² (23 mm × 27 mm). The proposed antenna has a desirable VSWR level, radiation pattern, radiation efficiency and gain characteristics which are suitable for wireless communication applications.     

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.     

Compact dual-frequency linear antenna with partial ground plane

In order to meet the need of multiband and antenna-in-package (AiP), a compact dual-frequency antenna with a partial ground and linear structure is proposed, optimised and realised. The proposed antenna was designed at 2.4 GHz and 5.8 GHz bands for WLAN applications. The total size of the antenna is 20 mm × 20 mm, equals to 0.27 λ_g1 × 0.27 λ_g1 and 0.65 λ_g2 × 0.65 λ_g2 (λ_g1, λ_g2 are the microstrip (with ground) guiding wavelengths at 2.4 GHz and 5.8 GHz) or 0.15 λ₀₁ × 0.15 λ₀₁ and 0.38 λ₀₂ × 0.38 λ₀₂ (λ₀₁, λ₀₂ are the wavelengths in the atmosphere at 2.4 GHz and 5.8 GHz). Also, omnidirectional radiation characteristics in the desired bands can be obtained.     

Internal Ultrawideband Monopole Antenna for Wireless USB Dongle Applications

A novel, ultrawideband (UWB) monopole antenna suitable to be mounted on the printed circuit board (PCB) of a wireless, universal, serial-bus (USB) dongle as an internal antenna is presented. The proposed antenna in the study is a U-shaped, metal-plate monopole antenna, easily fabricated from bending a simple metal plate onto a foam base of a compact size of 6times11times20 mm³. The antenna mainly comprises a pair of wide-ended radiating arms and a bevel-feed transition. When the antenna is mounted at the top portion of the PCB, one end of the radiating arm is also short-circuited to the system ground plane. With the proposed antenna structure, which can provide a very wide operating bandwidth of larger than 7.6 GHz, the antenna impedance bandwidth can easily cover the 3.1-10.6 GHz UWB band. Details of the antenna design are described, and experimental results of the constructed prototypes are presented and discussed     

ACS-Fed e-Shaped Dual Band Uniplanar Printed Antenna for Modern Wireless Communication Applications

A printed small size (12×16.5 mm) ACS-fed e-shaped uniplanar antenna is proposed for dual band applications. The multiband operating characteristics have been achieved by integrating e-shaped radiating strips to the 50ΩACSfeed line. Two simultaneously operating wide bands have been generated by using optimized radiating branch strips for the multiband applications. For obtaining size reduction and wider impedance bandwidth, e-shaped meandered elements are chosen in the design. The proposed design features the bandwidth (VSWR < 2, reflection coefficient below–10 dB) of 100 MHz in 2.4–2.5 GHz, and 2100MHzin 4.0–6.1 GHz. The developed multiband antenna can be useful for several wireless communication applications, such as 2.4 GHz Bluetooth/RFID,WLAN(2.4/5.2/5.8 GHz), WiMAX (5.5 GHz), US public safety band (4.9 GHz), ISM band, radio frequency energy harvesting and internet of things (IoT) applications.     

A compact quasi-self-complementary dual band notched UWB MIMO antenna with enhanced isolation using Hilbert fractal slot

A compact ultrawideband multiple input multiple output antenna with dual band notch characteristics is proposed. The design utilizes the property of quasi-self-complementary monopoles to achieve a bandwidth that ranges from 2.2 GHz to 11 GHz. The design has a compact size of 30 mm × 41 mm × 1.59 mm. Two quasi-self complementary half circular monopoles are symmetrically arranged to obtain MIMO antenna. Bandnotch characteristics are obtained by adding parasitic strips of Levy's Fractal shape near the feed line. A Hilbert Fractal shaped slot is etched in the ground plane to enhance the isolation (|S₂₁| < −20 dB) throughout the operational bandwidth. The measured and simulated radiation patterns are in good agreement and is found to be stable throughout the ultrawideband. Moreover, the measured peak gain is found to be 4 dBi.     

Cylindrical ring dielectric loaded horizontally polarized omnidirectional antenna for wideband radiation

A wideband horizontally polarized omnidirectional antenna with a cylindrical ring dielectric (CRD) loaded is proposed. Compared with the conventional alford-structure loop antenna (ASLA), the impedance and radiation pattern bandwidths are broadened by loading a CRD to the ASLA with two wing sections. The designed antenna is fabricated and measured, and good performance has been obtained. The measured reflection coefficient is less than −10 dB over the frequency band 1.63–2.8 GHz, i.e., 52.8%, which can cover 2G/3G/LTE band totally. The gain variation in all directions of horizontal plane is less than 1.4 dB in the whole band. The maximum gain is 1.56dBi throughout the operating band and it appears at 1.66 GHz. It is worth noting that the gain is around 1dBi and almost constant from 1.9 GHz to 2.7 GHz. Besides, the designed antenna has a compact size of 0.55λ × 0.55λ × 0.057λ, λ is for the lowest frequency of the operating band.     

一种应用于WLAN/WiMAX的新颖的三分枝单极天线

提出了一种应用于WLAN/WiMAX的新颖的多分枝单极天线,天线有三个分枝,结构紧凑,其大小为26mm×24mm×1.6mm,加工出了天线并进行测试,测试结果表明天线具有良好的双波段工作特性,｜S11｜≤-10dB时对应中心频率2.47GHz和4.825GHz处带宽分别达4%和62.4%,覆盖WLAN的2.4/5.2/5.8GHz频段及WiMAX的3.5/5.5GHz频段,同时采用了接地板开槽技术以调整带宽,天线在上述频段有近似于全向辐射方向图。     

Miniaturization of Dual‐Band PIFA for Wireless LAN Communication

In this letter, a simple method for reducing the size of a dual‐band planar inverted‐F antenna (PIFA) is described. This method is based on a coupling capacitor connected in parallel to the PIFA feed conductor. The proposed antenna occupies a small ground clearance of 10 mm×5 mm and is able to provide ?10‐dB impedance bandwidths of 120 MHz and 760 MHz for 2.45‐GHz and 5.5‐GHz wireless local area network applications, respectively. The measured antenna efficiencies are 71.8% and 73.6%, averaged over the 2.45‐GHz and 5.5‐GHz frequency bands, respectively.     

Multiband monopole antenna loaded with Complementary Split Ring Resonator and C-shaped slots

This paper presents a compact semi circular monopole antenna loaded with Complementary Split Ring Resonator (CSRR) and two C-shaped slots is proposed for Global System for Mobile Communication (GSM), Worldwide Interoperability for Microwave Access (WiMAX) and C-band applications. The size of the proposed antenna is 20 × 20 × 0.5 mm³. The resonance frequency of WiMAX (3.73 GHz) is achieved by introducing CSRR slots on the ground plane. To realize multiband characteristics for GSM (1.77 GHz), WiMAX (2.6 GHz) and C-band (4.15 GHz), two C-shaped slots of quarter wavelength are introduced in radiating element. The extraction procedure of negative permittivity for the proposed CSRR is discussed in detail. The proposed antenna is fabricated and measured. Simulated and measured results are in good agreement. Omni directional radiation pattern is obtained in H-plane and bi directional radiation pattern is obtained in E-plane. Parametric study of CSRR and C-shaped slot are examined to obtain best results. The proposed antenna has significant advantages, including low profile, miniaturization ability, and good impedance matching.     

Design of a CPW-Fed Compact MIMO Antenna for Next Generation Vehicle to Everything (V2X) Communication

This article presents a compact Co-Planar Waveguide (CPW) fed antenna for next-generation Vehicular Communications. The antenna is designed by employing two rectangular stacked patch structures and slots, making the antenna resonate at dual frequency bands. The analytical study of antenna design is carried out using the governing microstrip patch equations. On optimizing the patch's dimensions for CPW structures, the desired frequency range of operation is obtained for the single element antenna structure. The designed antenna resonates at 3.5 GHz (LTE-42 Band) and 5.9 GHz (DSRC Band), yielding this antenna to be a prime component for Vehicular to Everything (V2X) Communication. The optimized single-element antenna structure is 35 mm?×?20 mm designed on an FR-4 substrate of thickness 1.6 mm. The substrate has a dielectric constant of 4.4 and a loss tangent value of 0.001. Further, the antenna structure is developed as a 4-element MIMO configuration with the distance between adjacent antenna elements to be 10 mm. The adjacent antennas in the MIMO configuration are positioned orthogonal to each other, thereby exhibiting better isolation between the antenna elements. The antenna has a reflection coefficient value of?<??10 dB within the bandwidth of interest and VSWR less than 2. The Gain value of the designed antenna ranges between 2.8 and 2.9 dBi at 3.5 GHz and between 3.6 and 3.7 dBi at 5.89 GHz. The overall efficiency of the antenna element is between 60 and 80% at both frequency bands. MIMO parameters are analyzed by calculating the Channel Capacity Loss (CL), Diversity Gain (DG), Envelope Correlation Coefficient (ECC) and Total Active Reflection Co-Efficient (TARC). The designed antenna is fabricated and tested, which shows the measured results coincide with the simulated antenna results. The overall dimension of the MIMO configured antenna design is 60 mm × 60 mm × 1.6 mm, which is highly compact and is a suitable candidate for deployment of Vehicle to Vehicle (V2V), Vehicle to Infrastructure (V2I), and Vehicle to Network (V2N) scenarios.

     

Compact Triple‐Band Monopole Antenna for WLAN/WiMAX‐Band USB Dongle Applications

A miniaturized triple‐band antenna suitable for wireless USB dongle applications is proposed and investigated in this paper. The presented antenna, simply consisting of a circular‐arc‐shaped stub, an L‐shaped stub, a microstrip feed line, and a rectangular ground plane has a compact size of and is capable of generating three separate resonant modes with very good impedance matching. The measurement results show that the antenna has several impedance bandwidths for of 260 MHz (2.24 GHz to 2.5 GHz), 320 MHz (3.4 GHz to 3.72 GHz), and 990 MHz (5.1 GHz to 6.09 GHz), which can be applied to both 2.4/5.2/5.8 GHz WLAN bands and 3.5/5.5 GHz WiMAX bands. Moreover, nearly‐omni‐directional radiation patterns and stable gain across the operating bands can be obtained.