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.

     

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.     

Design and Analysis of Triple-Band Rectangular Microstrip Antenna Loaded with Notches and Slots for Wireless Applications

In this paper, a rectangular triple-band microstrip antenna has been designed for Bluetooth application by successively loading notches and slots of different dimension in radiating patch. The conventional microstrip antenna suffers with narrow impedance bandwidth. The current work affords an alternate option to enhance the bandwidth of antenna that resonates in triple-band operation. Initially, the antenna is resonating in single-band but after loading slots, the bandwidth of microstrip antenna has been obtained 1.97% (lower band), 10.35% (middle band) and 33.16% (upper band) resonating in triple-band with three resonant frequency at 1.422 GHz (lower resonant frequency), 1.791 GHz (middle resonant frequency) and 2.467 GHz (higher resonant frequency). The suggested antenna has upper frequency band in the range of 2.045–2.858 GHz resonating at 2.467 GHz frequency and it is appropriate for Bluetooth applications (2.40–2.48 GHz) and both lower band useful for other wireless (L-band) applications. The return loss of upper band is ??34.52 dB at 2.467 GHz. The suggested microstrip antenna is directly fed by 50 ohm microstrip line feed. The suggested antenna has been designed, simulated and analyzed by IE3D simulation software.

     

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.

     

Design and implementation of electromagnetic band‐gap embedded antenna for vehicle‐to‐everything communications in vehicular systems

We proposed a novel electromagnetic band‐gap (EBG) cell‐embedded antenna structure for reducing the interference that radiates at the antenna edge in wireless access in vehicular environment (WAVE) communication systems for vehicle‐to‐everything communications. To suppress the radiation of surface waves from the ground plane and vehicle, EBG cells were inserted between micropatch arrays. A simulation was also performed to determine the optimum EBG cell structure located above the ground plane in a conformal linear microstrip patch array antenna. The characteristics such as return loss, peak gain, and radiation patterns obtained using the fabricated EBG cell‐embedded antenna were superior to those obtained without the EBG cells. A return loss of 35.14 dB, peak gain of 10.15 dBi at 80°, and improvement of 2.037 dB max at the field of view in the radiation beam patterns were obtained using the proposed WAVE antenna.     

基于复合左右手传输线的2.45 GHz微带天线设计

基于复合左右手传输线基本原理, 提出了电磁带隙结构的双负媒质微带天线设计方法, 并制作了2.45 GHz的微带天线.该微带天线由2个单元的电磁带隙组成, 此电磁带隙结构经过优化采用非均匀结构, 可通过调整贴片尺寸和金属过孔半径来改变电磁带隙结构单元等效电路的并联部分电容和电感, 进而调节天线的谐振频率.设计并制作的微带天线其贴片整体尺寸为53.2 mm×19.8 mm, 在2.45 GHz的回波损耗为-32.6 dB, 方向图近似为8字形方向图, 最大增益为0.72 dB.仿真和测试的回波损耗、方向图符合得很好, 从而验证了这种设计方法的有效性.     

一种应用于ITS 的三频微带天线的设计*

设计了一种应用于智能交通系统(ITS)的三频微带天线,分别工作在GPS(1. 575GHz)、WLAN(2. 45GHz)以及DSRC(5. 8GHz)。采用堆叠结构实现大的双频比,其中顶层贴片工作在DSRC,底层贴片通过边缘处加 载四个相等矩形槽来实现双频。通过在方形贴片的一个对边边缘处加载两个相等的矩形槽来实现圆极化。通过调 整对角线上馈电点位置、平移顶层贴片以及改变底层贴片上的过孔大小来实现频带内的阻抗匹配。仿真和测试结 果表明吻合良好,该天线在三个频段内有着良好的阻抗匹配、轴比以及辐射方向图,能够满足设计要求。     

Design and Analysis of MIMO Antenna with High Isolation and Dual Notched Band Characteristics for Wireless Applications

A very compact Superwideband multiple-input–multiple-output antenna with dual notched band characteristics is presented. Superwideband characteristics is obtained by means of radiating patch and high isolation between two input ports are obtained by using T-shaped stub in ground plane. Two rejection bands (wireless interoperability for microwave access (WiMAX)/C-band and wireless local area network) are obtained by etching two elliptical slots on radiating patch. Antenna offers large measured useable bandwidth of 2.60–20.04 GHz. Diversity performance is studied in terms of envelope correlation coefficient, diversity gain and total active reflection coefficient. Antenna also offers desirable radiation pattern, gain and radiation efficiency which makes proposed antenna quite suitable for different wireless applications.

     

Beam-Steerable Ultra-Wide-Band Miniaturized Elliptical Phased Array Antenna Using Inverted-L-Shaped Modified Inset Feed and Defected Ground Structure for 5G Smartphones Millimeter-Wave Applications

Multi Input Multi Output (MIMO) and phased array systems are considered a key technologies to realize the 5G communication systems. Therefore, the purpose of this research is the suggestion of a novel mm-wave Ultrawide Band (UWB) antenna design with compact and straightforward layout suitable for both MIMO and phased array systems. Hence, the designed antenna array has been studied separately as a MIMO antenna and as a phased array antenna to carefully assess the performance of each system. The single antenna design is an elliptical patch antenna where the design novelty lies in the combination of a modified inset-feed and defected ground structure to provide a large bandwidth without any compromise in the radiation performance, nor in antenna size and design simplicity. The Design process are performed using CST MWS software, where the Rogers RT/Duroid 5880 substrate is chosen to construct the antenna. A broadband characteristic of 8.7 GHz from 26 to 34.7 GHz with two resonant frequencies at 28 GHz and 33 GHz is obtained. A good radiation properties are achieved, where the gain is greater than 4.5 dB while the radiation efficiency exceeds 97% over the operating band. The MIMO and phased array antennas are made up of 12-elements of the single UWB-antenna arranged linearly along the width-edge of the smartphone mainboard. The MIMO antenna proves a high diversity performance in terms of Diversity Gain (DG), Envelope Correlation Coefficient (ECC), Total Active Reflection Coefficient (TARC), Channel Capacity Loss (CCL) and Mean Effective Gain (MEG), owing to the low mutual coupling less than ??20 dB, which is obtained using a separating slits between the elements. In addition, the suggested phased array provides a highly stable gain up to 15 dB over the entire bandwidth at broadside direction, besides the wide scanning range of?±?60° at 28 GHz and?±?40° at 33 GHz. Hence, the attained results assure that the suggested antenna could be appropriate for incorporation in 5G smartphones and other wireless devices and can be effectively used for both phased array and MIMO applications.

     

基于反向并联二极管对的D波段次谐波混频器

设计并制作了一个D波段次谐波混频器。该混频器使用VDI公司反向并联肖特基二极管对,安装在50μm厚的石英基片悬置微带上。通过HFSS和ADS的联合设计仿真,混频器在射频频率141~158GHz频段内变频损耗低于10dB,在149 GHz处获得最佳变频损耗7.8dB。最后加工了实物并进行了测试,结果显示,在138~155GHz范围内,变频损耗基本小于20dB,带内最低损耗在10dB左右。该混频器具有结构简单,容易制造,变频损耗低等优点。     

A Quad Band Metamaterial Miniaturized Antenna for Wireless Applications with Gain Enhancement

This paper presents a designing of dual-coated miniaturized metamaterial inspired quad band antenna for wireless standards with gain enhancement. Proposed design has compactness in size with electrical dimension of 0.239?×?0.351?×?0.0127 λ (30?×?44?×?1.6 mm³), at lower frequency of 2.39 GHz. The antenna consist a double printed slotted hexagonal shape radiating section with implementation of metamaterial rectangular split ring resonator. Antenna achieve quad bands for wireless standards WLAN (2.4/5.8 GHz), WiMAX (3.5 GHz), IEEE 802.11P (WAVE-5.9 GHz), ITU assigned X bands (7.25–7.75, 7.9–8.4 GHz) and satellite communication systems operating bands (C-band: 7.4–8.9 GHz and X-band: 8–10 GHz for satellite TV). An acceptable gain, stable radiation characteristics and good impedance matching are observed at all the resonant frequencies of the proposed structure. By application of proposed frequency selective surface an average enhancement of gain is about 4–5 dB over the operating band. Antenna fabricated and tested represent good agreement between the simulated and measured results.

     

双频水平极化全向天线设计

分析并设计了一种双频水平极化全向天线,该天线采用印刷偶极子组阵形式实现全向辐射性能,采用双辐射臂形式以及梯形渐变线馈电,实现在2.4~2.5 GHz和5.1~5.9 GHz上回波损耗低于-10 dB的双频特性。低频增益1.2 dB,不圆度为0.2 dB;高频增益2.4 dB,不圆度为2 dB。该天线结构简单,拥有良好的全向性。     

一种适用于WLAN 的新型小型化双极化天线

设计了一种可工作于WLAN 2.4GHz频段的小型化双极化天线.该天线采用双层对称结构介质板,把辐射贴片四边分别切割成凸字形形状,实现了天线小型化和有效展宽天线带宽.同时在接地板开4个对称的十字形缝隙,进一步拓宽天线带宽和明显减小天线的整体尺寸并提高了天线辐射性能.由此设计制作的天线实验结果为:小于-10dB回波损耗的频段为2.37 ～ 2.59GHz,相对阻抗带宽达9.1％,端口隔离度达到了33dB,增益最大值约3.63 dBi,表明该微带天线具有宽频带和良好的辐射性能.此外,该天线结构简单紧凑,易于加工制作和集成,适合应用于移动终端.     

Design and Analysis of Dual-band Circularly Polarized Hybrid Ring Cylindrical Dielectric Resonator Antenna for Wireless Applications in C and X-Band

This article presents a dual-band circularly polarized hybrid ring CDRA (Cylindrical dielectric resonator antenna) for wireless applications in C and X-band. A circular ring inclusive of a slotted cross-shaped microstrip feed line is used to excite the ring CDRA and generation of HEM_11δ and TEM_01δ modes. Multiple inverted Z-shaped apertures and circular ring along with a slotted cross-shaped microstrip feed line are responsible for the generated circular polarization wave between 3.92 and 4.08 GHz in lower band and 8.85 to 9.61 GHz in upper band with 4% (160 MHz) and 8.23% (760 MHz) axial ratio bandwidth (ARBW) respectively. The proposed antenna also offers impedance bandwidth of 20.58% (780 MHz) between 3.40 and 4.18 GHz in lower band while 29.31% (2490 MHz) between 7.25 and 9.74 GHz in upper band resonating at 3.73 and 7.79 GHz with???26.4 and???35.61 dB return loss respectively. The proposed ring CDRA shows stable gain of peak value 5.8 dB (simulated) and 5.8 dB (measured) in lower band while 7.7 dB (simulated) and 8.2 dB (measured) in upper band.

     

Wideband to narrowband/dual band characteristics of monopole antenna using frequency selective surfaces

A monopole antenna having desirable transmission characteristics with high gain is proposed. The monopole antenna comprises 45° tilted square shaped patch and modified rectangular metallic ground plane on FR4 dielectric substrate. The proposed monopole antenna operates from 2.6 GHz to 9.7 GHz with maximum peak gain of 2.3 dBi. Now, a dual-layer aperture-type FSS is designed having a passband from 5.9 GHz to 9.2 GHz and incorporated with the proposed monopole antenna. Thus, the combination only covers the selective frequency band from 5.5 GHz to 8.7 GHz with a stable gain of around 5 dBi. Second, another FSS is designed, which has one stop-band from 4.1 GHz to 5.4 GHz and two passbands on the both sides of this stop-band. This combination does not work from 4.1 GHz to 5.5 GHz but covers dual band from 2.48 GHz to 3.3 GHz with a peak gain of 5 dBi and 5.5 GHz to 10 GHz with a peak gain of 5.5 dBi. Therefore, without modifying the antenna design, any tunable transmission band can be achieved by the proposed combination. The proposed antenna and FSS combination structure may be suitable for military wireless applications for its band selection characteristics.     

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.

     

Dual-Band Antenna Array with Reduced Mutual-Coupling for Wearable Wireless Communication Applications

In this paper, dual-band wearable microstrip patch antenna printed on FR4-substrate is designed and fabricated for wearable wireless communications. A star-shaped monopole Ω antenna connected to 50 Ω transmission line, backed by partial ground plane is used. The antenna dimensions are optimized for wideband radiation characteristics. Different types of dielectric substrates are investigated for wideband wearable applications. The proposed antenna printed on jeans textile substrate introduces an impedance matching bandwidth of 7.3 GHz with maximum gain of 5 dBi. The effect of mutual coupling between two parallel patches, two opposite patches and two orthogonal patches on their radiation characteristics are investigated. High isolation is achieved for two orthogonal patches placed away from each other by 0.3λ with a rectangular strip etched between them and cutting in the ground plane. The isolation is below ? 29 dB within the frequency band. The structure achieves impedance matching bandwidth of 1.8 GHz in 1st-band and 4.8 GHz in 2nd-band with maximum gains of 8.5 dBi and 5.3 dBi, respectively. A prototype element is fabricated, measured and the radiation characteristics coincide with the simulated results. The structure is simple, light-weight, and is suitable for WAN applications in the frequency band from 2 GHz to 7 GHz. The effect of human body tissue on the radiation characteristics of the antenna array is investigated. 

     

Narrow and wide band monopole antenna design using heterogeneous bidirectional recurrent neural network for LTE and UWB applications

The proposed antenna is a small wideband monopole with wideband circular polarization using heterogeneous bidirectional recurrent neural network for both narrow and wide band applications (NWB-MAD-HBRNN). The electromagnetic structure is designed, fabricated, and simulated with 1 mm thickness on FR4 substrate material along dielectric constant 4.3. The proposed antenna includes 4.3–8.85 GHz for ultrawideband applications; it contains reconfigurable narrow band for L-band 1.27 GHz, LTE, and ultrawideband applications. To enhance the antenna impedance bandwidth (BW) along axial ratio bandwidth (ARBW), a slit is etched at the antenna patch, a rectangular stub is inserted into the ground plane, and semicircular stub is added to the top of antenna feed line. The better agreement is observed in the measured and simulated gain performance of 4.8 dB for LTE band applications. The proposed NWB-MAD-HBRNN design provides 13.50%, 18.91%, and 22.58% higher bandwidth and 18.36%, 20.38%, and 27.58% lower return loss than the existing designs, such as bio-inspired wideband antenna for wireless applications based on perturbation technique (BWA-WA-PA), a compact circularly polarized modified printed monopole antenna for wireless applications (CCP-MPMA-WA), and new multiband monopole antenna for certain broadband wireless applications along wireless personal communications (PA-MMA-BWA), respectively.     

宽带E型贴片天线的设计

本文在矩形微带贴片天线的基础上,通过在贴片上开两条对称的缝隙而得到E型贴片天线.经过仿真优化计算出E型贴片天线的尺寸,确定了最终方案模型,得到了方向图、回波损耗等参数.设计的天线工作频率为1.88GHz到2.4GHz,带宽达25.2％,谐振频率的增益达9.38dB.该天线拥有结构简单、体积小、宽频带特点,具有很好的实际...