Small Printed Ultrawideband Antenna With Reduced Ground Plane Effect

A small printed antenna is described with a reduced ground-plane effect for ultrawideband (UWB) applications. The radiator and ground plane of the antenna are etched onto a piece of printed circuit board (PCB) with an overall size of 25mmtimes25 mmtimes1.5 mm. A notch is cut from the radiator while a strip is asymmetrically attached to the radiator. The simulation and measurement show that the miniaturized antenna achieves a broad operating bandwidth of 2.9-11.6 GHz for a 10-dB return loss. In particular, the ground-plane effect on impedance performance is greatly reduced by cutting the notch from the radiator because the electric currents on the ground plane are significantly suppressed at the lower edge operating frequencies. The antenna features three-dimensional omni-directional radiation with high radiation efficiency of 79%-95% across the UWB bandwidth. In addition, a parametric study of the geometric and electric parameters of the proposed antenna will be able to provide antenna engineers with more design information     

Printed Planar Antenna for Wideband Applications

A compact planar antenna operating at a frequency range of 3–16 GHz is presented for wideband applications. The antenna is composed of a square patch fed by a microstrip line and a partial ground plane with a rectangular slot. The proposed antenna is very easy to be integrated with microwave circuitry for low manufacturing cost. The flat antenna has a compact structure and the total size is 29 mm × 22 mm. The result shows that the measured impedance bandwidth (VSWR≤ 2) of the proposed antenna is 3.2–15.44 GHz, with a notch from 4.7 to 5.8 GHz. The effects of the structure parameters on impedance bandwidth are also investigated. Details of the proposed compact planar antenna design are presented and discussed.     

Design of a Multiresonator Loaded Band-Rejected Ultrawideband Planar Monopole Antenna With Controllable Notched Bandwidth

We present a new multiresonator loaded band-rejected planar monopole antenna for ultrawideband applications. The proposed microstrip-fed antenna is composed of a flared metal plate, a truncated ground plane, and two pairs of folded strips. By applying the resonance nature of the folded strips and the associated cross coupling effects, the proposed antenna demonstrates bandstop-filter-like response with bandwidth controllability at the targeted rejection band. To illustrate the antenna operating mechanism more clearly, an equivalent circuit model consisting of RLC lumped resonators and J-inverters is discussed and extracted. The antenna input admittance calculated with the help of the equivalent circuit model agrees reasonably well with the simulated one obtained by the full-wave simulator. The design concept and the simulated and experimental results including the return losses, radiation patterns, and gain responses versus frequencies are carefully investigated throughout the paper. A parametric study in terms of the bandwidth tunability of the proposed design at the notched band is performed. The effects of the finite size ground plane are studied in this paper as well.      

A Dipole Excited Ultrawideband Dielectric Rod Antenna With Reflector

A novel very compact ultrawideband dielectric rod antenna with metallic reflector is presented. The desired HE11 mode on the rod is excited by a biconical dipole fed by a broadband tapered microstrip line balun. The input reflection remains below -10 dB from 3 up to 20 GHz. The antenna exhibits a flat gain larger than 7 dBi over the whole ultrawideband frequency range from 3 to 10 GHz approved by the Federal Communication Commission. An almost constant transient performance over a wide azimuth angle of plusmn40deg is obtained with small dispersion.     

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.

     

A Novel Compact Ultrawideband Antenna

In this paper, novel compact ultrawideband (UWB) antennas are proposed and successfully demonstrated within the bandwidth with the ratio of the maximum and minimum frequency to be more than 30. The results from electromagnetics (EM) simulation and measurement show good agreement. From the EM simulation results, the electromagnetic wave could be radiated to the free space through the antenna only if the antenna impedance were matched to one of its feed systems within the bandwidth. The developed antenna with a small size of 17 $times$ 17 $times $ 12 mm$^{3}$ shows voltage standing wave ratio (VSWR) of less than 2.5 : 1 from 3 to 100 GHz for the simulated data, and less than 2 : 1 from 3 to 50 GHz for the measured data. The gain of the developed antenna is more than 2 dBi from 3.1 to 10.6 GHz in the application of high-speed wireless digital communication system.      

A Single-Layer Ultrawideband Microstrip Antenna

A single-layer microstrip antenna for ultrawideband (UWB) applications, in which an array of rectangular microstrip patches was arranged in the log-periodic way and proximity-coupled to the microstrip feeding line, is presented. In order to reduce the number of microstrip patches in the UWB log-periodic arrays, a large scale factor ${rm k}=1.1$ was firstly reported and proved to be highly effective. Furthermore, instead of using an absorbing terminal loading, a novel loss-free compensating stub was proposed. Detailed parameters study was also presented for better understanding of the proposed antennas. The impedance bandwidth (measured ${rm VSWR}≪2.5$ ) of an example antenna with only 11 elements is from 2.26–6.85 GHz with a ratio of about 3.03:1. Both numerical and experimental results show that the proposed antenna has stable directional radiation patterns, very low-profile and low fabrication cost, which are suitable for various broadband 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.     

Triple Band Dual Polarized CPW-Fed Planar Monopole Antenna

Wireless Personal Communications - This article presents a novel, simple and planar design of a CPW-fed tri-band and dual polarized monopole antenna. The proposed structure includes inverted...     

Analysis of Planar Ultrawideband Antennas With On-Ground Slot Band-Notched Structures

Planar ultrawideband (UWB) antennas with on-ground band-notched structures are studied in this paper. Two different slot resonators, which feature quarter-wavelength and half-wavelength configurations, are embedded into the arc shaped ground plane of the circular disk patch antennas in order to obtain the desired band-rejection around 5.8 GHz. Their principles and characteristics are analyzed and compared in detail providing designers with in-depth understanding and useful design information. By choosing the quarter-wavelength slot resonator, the first spurious stopband can be pushed up to 3 $f _{0}$ ($f _{0}$ stands for the center frequency of the notch) and this antenna retains a super wide working band which spans from 1.62 GHz to 17.43 GHz. Performance in both the frequency domain and time domain for this antenna has been investigated carefully. The transmission response of a transceiving antenna system and their corresponding transient analysis are discussed at the end of this paper.      

天线增益频带特性确定的一种简单方法

介绍了用卫星源法测量卫星通信地球站天线的特点。简述了利用3dB和10dB波束宽度确定地球站天线增益的原理和方法。提出了利用外推法确定天线增益频段特性的一种简单方法。对波束宽度法测量增益的误差进行了分析和估算,其均方根误差±0.387dB。最后给出了某工程应用的C波段15m地球站天线增益测量结果,增益测量结果与理论计算结果吻合很好。     

Miniature Antenna Using Printed Coupled Lines Emulating Degenerate Band Edge Crystals

A miniature printed antenna design that exploits higher-order dispersion behavior in degenerate band edge (DBE) crystals is proposed. First, the unit cell of a DBE crystal is emulated using a simple combination of uncoupled and coupled microstrip (MS) line sections printed on a low loss dielectric substrate. Subsequently, a resonant antenna is formed by cascading two such MS-DBE unit cells in a circularly periodic fashion. The first part of the paper is devoted to the antenna/array design and characterization using a low contrast dielectric substrate (Rogers Duroid, $epsilon _{r}=2.2$). Next, fabrication and design verification using a high dielectric constant substrate (alumina: ${rm Al}_{2}{rm O}_{3}$, $epsilon _{r}=9.6$) is given. The manufactured antenna was measured to have a broadside gain of 4.5 dB at 1.48 GHz with 3.0% bandwidth. For this gain and bandwidth, we demonstrate that the proposed MS-DBE antenna has a $lambda _{0}/9 times lambda _{0}/9$ footprint and is among the smallest in the literature.      

Ultrawideband Double Rhombus Antenna With Stable Radiation Patterns for Phased Array Applications

A broadband microstrip-fed printed antenna is proposed for phased antenna array systems. The antenna consists of two parallel-modified dipoles of different lengths. The regular dipole shape is modified to a quasi-rhombus shape by adding two triangular patches. Using two dipoles helps maintain stable radiation patterns close to their resonance frequencies. A modified array configuration is proposed to further enhance the antenna radiation characteristics and usable bandwidth. Scanning capabilities are studied for a four-element array. The proposed antenna provides endfire radiation patterns with high gain, high front-to-back (F-to-B) ratio, low cross-polarization level, wide beamwidth, and wide scanning angles in a wide bandwidth of 103%     

一种宽频带印刷缝隙天线

通过对花瓣形天线和单极子天线的研究,设计了一款超小型印刷缝隙天线,该天线的工作频宽为4.8~31.5GHz,基本覆盖SHF频段.在此频段该天线具有稳定的增益,且波形保真特性良好.该天线尺寸小,成本低,且易于与其他电路集成,是无线通信收发天线的一个很好的选择.     

Compact Planar Monopole Antenna with Dual Band Notched Characteristics Using T-Shaped Stub and Rectangular Mushroom Type Electromagnetic Band Gap Structure for UWB and Bluetooth Applications

In this paper, an ultra-wideband (UWB) antenna with dual band-notched characteristics is proposed. The proposed antenna also covers ISM (Industrial, Scientific, and Medical)/Bluetooth band. The antenna consists of a microstrip fed truncated U-shaped patch, T-shaped stub, rectangular mushroom type electromagnetic band gap structures (EBG), and partial ground plane. To mitigate the problem of interference due to standard narrow bands (like wireless interoperability microwave access (WiMAX) and wireless local area network (WLAN)) lie in the range of UWB, dual band notched characteristics is introduced. The WiMAX and WLAN band notched characteristics are realized by introducing a T-shaped stub and rectangular mushroom type EBG structures, respectively. The proposed antenna is printed on a 1.6 mm thick FR4 substrate with relative permittivity \((\upvarepsilon _{\mathrm{r}})\) 4.4 and the size of actual antenna is \(36 \times 40\hbox { mm}^{2}\) . The measured results shows that the proposed antenna attains a wide impedance bandwidth \((\hbox {VSWR} \le 2)\) from 2.35 to 11.6 GHz with dual band notched characteristics from 3.29 to 3.9 GHz and 5.1 to 5.85 GHz with stable radiation patterns. The time domain behaviors of the proposed antenna is also analyzed for pulse handling capability.     

Ultrawideband PIFA With a Capacitive Feed for Penta-Band Folder-Type Mobile Phone Antenna

An ultrawideband planar inverted-F antenna (PIFA) with a capacitive feed in the folder-type or clamshell mobile phone for penta-band operation is presented. The antenna is placed at the hinge position between the main and upper ground planes of the folder-type mobile phone. With the use of the capacitive feed, a very wide operating bandwidth (3:1 VSWR or 6-dB return loss) of about 1.5 GHz (from 820 to 2345 MHz) is obtained, although the antenna is with a small radiating plate of size $8times 40 {rm mm}^{2}$ and a low profile of 7.8 mm above the top edge of the main ground plane. The very wide bandwidth covers GSM850/900/1800/1900/UMTS penta-band operation for the mobile phone in the open (talk) state. In addition, when in the closed (standby) state, although the groundplane condition greatly differs from that in the open state, the impedance matching over the operating bands can still be better than 6:1 VSWR (3-dB return loss), acceptable for standby operation in the practical applications.      

小型化宽带宽波束四臂螺旋天线

文章提出一种应用于卫星移动通信系统的小型化宽带宽波束印刷四臂螺旋天线结构,每组辐射振子分成两个支路,分别以不同的长度、宽度和螺旋角度绕制以减少振子间的耦合、提高带宽。该天线的宽频带、宽波束能适用于卫星通信手持终端系统的应用。     

矩形腔十字裂缝天线

随着卫星移动通信技术的发展,一种能适合机载和地面移动载体卫星通信的天线越来越受到人们的青睐。该种天线应具有宽频带、圆极化和电扫描跟踪等特性,而矩形腔十字裂缝天线就是该种天线理想的辐射单元之一。基于矩量法分析,本文提出了计算矩形腔十字裂缝天线的数值方法,给出了天线单元的输入阻抗、增益和轴比等辐射特性的数值结果,进行了实验验证。验证表明,理论和实验结果有着很好的一致性。     

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.     

小型超宽带平面天线阵列设计与优化

提出了一种小型超宽带(UWB)平面天线阵列并进行了优化.首先设计了两个不同的UWB天线单元方案:印刷天线-Vivaldi天线、平板天线-平面螺旋天线,并通过对比选择螺旋天线单元作为组阵单元.对该天线阵列的回波损耗、3D辐射图、方向图进行了仿真计算和设计.结果该天线阵列在6 ～ 10GHz内具有较好的定向辐射特性,增益达到15dB.进一步优化单元空间分布结构,使天线在相应频段内具有更佳的方向性.通过调整各个馈源的相位差,在不失去增益的同时,可以控制波束的偏转.