A narrow-frame antenna for WWAN/LTE/WiMAX/WLAN mobile phones

In this paper, we present a novel narrow-frame antenna with a size of 75 × 8 × 5.8 mm³ for 5.7 in. mobile phones. The antenna mainly consists of a monopole with four branches that are coupled to a two-branch grounded strip. Our antenna is able to cover more bands than other narrow-frame antennas by excitation of several resonant modes. The improved range of the antenna covers the following eleven bands: LTE700, GSM850, GSM900, DCS, PCS, UMTS, LTE2300, LTE2500, LTE3400 (3400–3800 MHz)/WiMAX3.5 GHz (3400–3650 MHz), WLAN5.2 GHz (5150–5350 MHz) and WLAN5.8 GHz (5725–5875 MHz). Another advantage of the proposed antenna is that it does not need any lumped element to match the antenna. The working principles of the proposed antenna are thoroughly studied. A prototype of the proposed antenna is fabricated and measured, with the results in good agreement with the simulation results.     

A high gain dual-band printed antenna for LTE base stations with a corner reflector

A high gain dual-band printed antenna is proposed for LTE base stations applications. The established 60 × 60 mm² broadband antenna structure is composed of two perpendicular U-shaped and L-shaped monopole antennas which are located vertically on ground plane printed on 1.6 mm thick FR4 substrate. A metallized wall is connected to the substrate which forms a corner reflector. A coaxial cable at the common center of the monopoles is adopted to excite the antenna. Wise implementation of the conductive elements and finely tuning of the monopoles dimensions yield the excitation of two resonances and dual band operation achievement. The presented antenna achieves bandwidths of 1.61–1.86 GHz and 2.25–2.45 GHz suitable for LTE applications. Stable radiation pattern, small size, cost effective fabrication, and high peak gain values of 10 dBi and 9.5 dBi at two operating bands are the prominent features of the proposed antenna topology.     

一种宽频带双极化印刷偶极子基站天线

设计并优化了一款适用于LTE天线系统的基站天线振子单元。在印刷偶极子天线以及微带巴伦的基础上,通过等效电路模型进行分析,设计出该天线的多级阻抗匹配巴伦。采用寄生贴片、领结型设计等技术,有效地拓展了天线频带带宽,实现了±45°双极化。仿真结果表明,天线的VSWR≤1.5和回波损耗大于15 d B的带宽达到了54.5%,可以覆盖GSM1800,CDMA2000,WCDMA,TD-SCDMA和LTE系统。在此频带范围内,该天线的驻波特性、方向性、增益和隔离度等指标均满足LTE多模式系统的指标。同时该天线也易于制作,适用于LTE多模式基站天线系统。     

Design and optimization of a non-cross feed printed log periodic dipole array antenna using particle swarm optimization

This paper presents an optimized design of non-cross feed Printed Log Periodic Dipole Array (PLPDA) antenna using Particle Swarm Optimization (PSO) technique. An improved feed structure of non-cross fed dipoles is chosen as reference antenna, which avoids the complexity of conventional feeding with long coaxial line and CPW feed. A simple fitness function based on S₁₁ parameter is used in PSO to achieve the goal of size reduction and bandwidth enhancement. Simulation results on CST software are verified by a manufactured prototype of proposed PSO optimized non-cross feed PLPDA antenna using FR 4 substrate with a thickness of 1.6 mm. The measured bandwidth of proposed antenna is 4.2–11.6 GHz with a fractional bandwidth of 93.6%, whereas the reference antenna covers the frequency range from 4.2 to 9.2 GHz with a fractional bandwidth of 74.6%. The effective area of the proposed design is 30% lesser than reference antenna. Proposed antenna is offering peak gain of 7.6 dBi with an average gain of 5.5 dBi in desired band. The electrical size of optimized structure is 0.53λ at center frequency. Thus, proposed antenna is offering higher bandwidth and significantly smaller size with less complexity and lower cost, while maintaining the log periodic nature and gain.     

A dual-band multiple-input multiple-output microstrip antenna with metamaterial structure for LTE and WLAN applications

A method to enhance the gain of microstrip dual-band multiple-input multiple-output (MIMO) antenna using partially reflective surface (PRS) layer is introduced and investigated in this paper. The proposed antenna consists of two FR4 substrates. The lower substrate has two radiating patches with parasitic elements that are supplied independently and create the MIMO property of the antenna. The upper substrate which is known as superstrate is arrays of PRS unit cells. The PRS layer printed on either side of a dielectric substrate and causes the antenna gain to increase in both frequency bands. The proposed antenna is appropriate for LTE (2.4–3.1 GHz) and WLAN (5.1–5.8 GHz) applications. The measured values of S₁₁ and S₂₂ parameters of the antenna are less than −10 dB and its FBR and gain are 12.5 dB and 5dBi, respectively. The average half power beam-width (HPBW) is roughly 108^○.     

LTE基站天线阵列设计

天线是移动通信系统的关键硬件设备之一。随着移动通信技术的飞速发展,系统越来越复杂,对天线性能的要求也越来越高。LTE作为第三代通信技术(3G)的长期演进技术,必将在未来的一段时间内对现代通信产生更大的影响,因而对于天线的工作频段、带宽、波束等相关指标也提出了更高的要求。对LTE频段±45°双极化宽带天线单元进行组阵设计和仿真分析,结果表明了该天线阵列工作性能良好。     

An offset CPW-fed triple-band circularly polarized printed antenna for multiband wireless applications

An offset coplanar waveguide (CPW)-fed triple-band circularly polarized tilted asymmetrical E-shaped printed antenna for multiband wireless applications is presented in this paper. The antenna mainly consists of a tilted asymmetrical E-shaped patch and excite by a 50 Ω offset CPW feed line using a transformer for impedance matching to generate wide quad operating bands. By properly embedding rectangular slots in the tilted asymmetrical E-shaped patch and triangular stubs loaded modified CPW ground plane, the antenna reveals triple-band circular polarization (CP) features. Numerical analysis and experimental validation of the antenna structure have been carried out and results are presented. The mechanism of triple-band CP operation, analysis of surface current distributions, design procedure, and parametric study of the design is discussed in details. It is well suited for the application of UMTS-2100, 3.5/5.5 GHz WiMAX, 5.2/5.8 GHz WLAN, ITS, downlink of X-band satellite communication, and ITU 8 GHz bands.     

车载电话用双频共面振子天线的设计

设计了一个用于车载电话的双频共面振子天线.为获得在同轴馈电时天线振子的平衡馈电,该设计使用了共面波导馈电结构.仿真计算结果给出了天线振子双臂的电流分布,并显示设计的共面振子天线在两个不同的频率上工作.实际设计天线的测试结果表明,在两个频带824MHz～896MHz和1850MHz～1990MHz内,设计天线的驻波比都小于2,而在水平面内的平均增益都大于指标值.     

A HORIZONTAL SMALL SIZED BACKFIRE ANTENNA USING CIRCULAR DIPOLE

In this paper,a horizontal small sized(≈0.5λ)backfire antenna with the circulardipole is described.The antenna structure and experimental results are given.The experimentalresults demonstrate that the antenna has better electrical performances.     

面向RFID应用的几种2.45 GHz微带天线的分析比较

随着RFID的广泛应用,微带天线已经成为RFID中不可缺少的一部分,常见的微带天线有单偶极子和双偶极子天线。根据目前RFID的应用,提出了几种基于2.45 GHz的板载天线,同时结合天线的基本理论对这几种结构进行了分析,并通过HFSS软件进行仿真比较。通过对仿真结果的分析,讨论了各种微带天线的优缺点,为RFID的应用提供了参考。     

Soft computing-based synthesis model for equilateral triangular ring printed antenna

A soft computing-based synthesis model is proposed for the design of equilateral triangular ring printed antennas (ETRPAs) that operate at ultrahigh band applications. The synthesis of printed antennas having irregular shapes needs great efforts and time. Soft computing models eliminates complex, lengthy and time consuming mathematical procedures for synthesis and analysis of the printed antennas. In this paper, a soft computing model based on artificial neural network (ANN) is constructed for synthesis of ETRPAs. To generate training and testing data set, number of 100 ETRPAs with various geometrical and electrical parameters are simulated in terms of resonant frequency with the aid of a 3D full wave simulator. Soft computing model based ANN is designed to obtain the patch physical dimensions of ETRPAs simultaneously. The soft computing model is trained with simulated data set of 75 ETRPAs and tested with remainders 25 ETRPAs. A prototype of ETRPA is then fabricated to verify the proposed model. The testing results of the soft computing model are found in close agreement with simulated and experimental data. The presented model is simply/fast predicting the patch dimensions of ETRPAs and it is extremely useful to antenna engineers for the design of the ETRPAs.     

Miniaturized wideband dual linearly and circularly polarized printed square slot antenna for multiradio wireless systems

A dual symmetrical coplanar waveguide (CPW)-fed small size wideband printed square slot antenna (SSA) with dual linearly and circularly polarized radiation capability is presented. The antenna is composed using a square slot, two symmetrical orthogonal CPW feed lines connected to horizontal and vertical arm of L-shaped radiator, an embedded parasitic inverted-L strip at the lower left corner of the square ground slot and engraving slots in the ground plane. Circular polarization (CP) is achieved due to two orthogonal CPW feed lines and a common L-shaped radiator. Isolation between ports is improved by engraving slots at the lower left corner of ground plane and embedded parasitic inverted-L strip. The sense of dual-polarization can be changed in pass-band by changing the port excitation. Measured antenna reveals that an 84.4% (4.6 GHz, 3.15–7.75 GHz) −10 dB impedance bandwidth (IBW) and about 33% (2.03 GHz, 5.12–7.15 GHz) 3-dB axial ratio bandwidth (ARBW). Isolation between ports <−16 dB is achieved over usable CP band.     

A simple design of planar microstrip antenna on composite material substrate for Ku/K band satellite applications

A straight forward design of rectangular slotted microstrip planar antenna fed by 50 ohm microstrip line is proposed for Ku/K band satellite applications. The radiating patch of the antenna occupies an area of 17 × 17 mm² and fabricated on 1.0 mm‐thick ceramic filled bioplastic composite material substrate whose dielectric constant (ε_r ) is 10.0. The dual resonant square‐shaped antenna has been formed by inserting four arc shape slots at the corners with the combination of circle and square and wide square shape slot at the center. The results from the measured data show that the antenna has a lower resonant mode impedance bandwidth for S11 < −10 dB is of 18.4% (11.67–14.05 GHz) and upper resonant mode bandwidth is of 8.2% (18.19–19.75 GHz) centered at 12.94 GHz and 19.04 GHz, respectively. The antenna prototype has achieved maximum gains of 3.1 dBi and 4.13 dBi with average radiation efficiencies of 75.3% and 86.4% for the lower band and the upper band, respectively. The numerical data analyses of both the measured and simulated results show relatively good agreement. Moreover, the consistent and symmetrical radiation patters of the proposed antenna make it suitable candidate for the Ku/K band satellite applications. Copyright © 2015 John Wiley & Sons, Ltd.     

一种新型的GSM/DCS印刷贴片天线单元

双频段印刷天线在移动通信中有着广泛的应用.本文提出了一种新型的GSM900/DCS1800双频段单层贴片天线,用传输线模型对该天线进行了理论分析、用Ensemble 8.0软件进行了仿真、并用Optimetrics 2.0软件进行了优化,实验结果和计算机仿真结果有着很好的一致性.     

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.     

LTE系统中一种改进的天线端口数检测算法

在长期演进( LTE)系统中,发送天线端口数通过循环冗余校验掩码的方式隐含于物理广播信道( PBCH)中,终端在解读PBCH信道获取主信息块( MIB)的同时,需要正确检测PBCH采用的发送天线端口数。传统的检测方法尝试分别用1、2、4等3种发射天线数进行PBCH译码,直至正确译码为止,译码复杂度非常高。基于此,提出一种改进的天线端口数估计算法,提取各天线端口传输的小区参考信号序列做相关,通过相关值与相关系数门限值的比较直接快速获取基站的实际天线端口数。仿真结果表明：该算法相较于传统检测算法和功率检测算法在时间复杂度上分别提升了4个数量级和3倍;在信噪比高于0 dB时,所提检测算法较功率检测算法有4~6 dB的增益。     

A novel wideband and circularly polarized cross‐dipole antenna

In this paper, we present a novel wideband circularly polarized (CP) composite, called cavity‐backed crossed dipole antenna for 2.45 GHz industrial, scientific, and medical (ISM) band wireless communication. To excite the CP radiation effectively, a curved‐delay line providing an orthogonal phase difference among the cross‐dipole elements is attached at corners of the sequentially rotated elements. By choosing a proper radius of the curved‐delay line, a wide input impedance of the antenna can be realized. Unlike conventional cross‐dipole antennas, the proposed cross‐dipole antenna is designed with an open stub added to the radiating arms of the dipole so that both impedance and axial ratio bandwidths are enhanced. The antenna is center‐fed by a 50‐Ω coaxial cable and is placed above a cavity‐backed reflector to obtain a directional CP radiation pattern. With the advantage of being center‐fed, a symmetric CP radiation pattern can be achieved across the entire operating bandwidth. To further improve the directivity and the radiation pattern, a rectangular cavity‐backed reflector is used. Simulated and measured results confirm that the proposed antenna has good CP characteristics. The proposed antenna obtains a broad 3‐dB axial ratio bandwidth of 49% (1.20 GHz, 1.96–3.16 GHz) and an impedance bandwidth of 67.7% (1.66 GHz, 1.69–3.35 GHz) for reflection coefficient (S₁₁) ≦ −10 dB. It also yields an average CP gain of 9.2 dBic across the operating bandwidth and a peak CP gain of 10 dBic. Copyright © 2016 John Wiley & Sons, Ltd.     

A dual polarized antenna on a novel broadband multilayer Artificial Magnetic Conductor backed surface for LTE/CDMA/GSM base station applications

The paper presents a low profile dual polarized dipole antenna topology backed by a novel broadband multilayer Artificial Magnetic Conductor (AMC) based reflecting surface. The antenna consists of a pair of square loop shaped dipoles with T-shaped feed structures arranged orthogonally to provide dual slant polarizations at ±45°. The antenna structure is backed by a novel multilayered AMC structure consisting of stacked square patches with via connected at middle and an air filled ground plane at the bottom. Experimental results show that the proposed antenna operates from 700 to 1000 MHz with bandwidth of 35% and an average gain of 8.5 dBi over the bandwidth. The Simulated and measured results of the antenna structure indicate the antenna to be suitable for interoperable Long Term Evolution (LTE), Code Division Multiple Access (CDMA) and Global System for mobile communications (GSM) applications.     

A compact wide slot antenna with dual band-notch characteristic for ultra-wideband applications

A new type of ultra-wideband (UWB) antenna with a dual-notched frequency band, compact size of 21?×?28?mm² and a coplanar waveguide (CPW) fed is proposed in this article. Two notched frequency bands are obtained by embedding two U-shaped slots in the radiation patch and a rectangle slot in the ground plane, which can be controlled by adjusting the length of the responding slots. The frequency domain characteristics are investigated and measured. Both the experimental and numerical results show that the proposed antenna has an impedance bandwidth ranging from 3.1?GHz to more than 11.0?GHz in which voltage standing wave ratio is less than 2, expect two notch frequency band, 5–6?GHz (WLAN) and 7.7–8.5?GHz (X-band for satellite communications in China).