一种新型UWB平面单极子微带天线阵的设计

提出了一种新型平面单极子微带天线阵,以平面矩形单极子天线为原型,通过改变辐射贴片的形状实现对原有天线性能的优化。设计了中心频率为2.4 GHz,相对带宽是42%,增益达13 dBi的宽频带四单元平面单极天线阵。通过仿真与实验表明,该天线在1.93 GHz~2.93 GHz频带内反射系数均小于-10 dB。     

具有高带外抑制特性的滤波器天线集成设计

利用滤波器综合设计方法设计了一款新型的具有高带外抑制性的微带滤波器天线。滤波器天线由五个开口谐振环、平行耦合线和倒L 天线组成。设计思路是使用倒L 天线代替滤波器的最后一个谐振器,然后利用平行耦合线等效为导纳变换器将谐振器与天线进行耦合,从而设计出既有滤波性能又有辐射性能的滤波器天线。滤波器天线采用交叉耦合结构,在带外有两个传输零点,大大提高了滤波器天线的带外抑制能力。滤波器天线经过仿真和测试,结果显示其反射系数S11 <-10 dB 的相对带宽为8%(2.37 ~2.57 GHz),带内增益约1.6 dBi,传输零点在带外50 MHz 处,增益下降到-25 dBi,带外整体下降到-20 dBi 以下,带外抑制特性显著。     

串联邻近耦合馈电微带天线阵列的设计

针对高增益、高效率的微带天线需求,将邻近耦合馈电引入串馈微带阵列,提出两种串联谐振微带天线阵列设计。首先研制出1??16元低副瓣串联天线阵列,工作频率35 GHz,测试得到增益为17.3 dBi,带宽4.3%,副瓣电平-17.6 dB。在上述馈电方式中引入U型谐振器及馈电缝隙,提出一种串联邻近耦合馈电的双频正交极化天线阵列,中心频率分别为4.5 GHz和5.0 GHz,两个频带内带宽分别为5.0%和7.8%,隔离良好,中心频率处增益为7.6 dBi和8.2 dBi。这种馈电方式便于组成高效率的大阵列,同时具有良好带宽,在实现多功能共口径阵列中具有独特优势。     

对称L型缺陷微带结构可调带通滤波器研究

设计了一种由对称L型缺陷微带结构实现的新型频率可调带通滤波器,并给出了相应的等效电路;对具有该结构的单频带带通滤波器的S参数频响特性进行了仿真与分析,并计算了耦合系数;依据上述结构设计制作了一种可调谐的双频带带通滤波器,并对其谐振频率的可调性进行了分析。结果表明:所制滤波器的谐振频率分别为2.4 GHz和3.5 GHz,相对带宽分别为4.63%和4.95%,有效电路尺寸仅为26.0 mm×1.2 mm。该L型缺陷微带结构带通滤波器具有结构简单紧凑、尺寸小、频率选择性好和谐振频率独立可调等优点。     

S波段传输零点可控的双频滤波功分器

为了更好地满足无线通信系统对微波电路双频/多频段的需求,基于微带-槽线双层结构设计了一款应用于S波段的双频滤波功分器。首先,在单个半波长微带谐振器基础上,利用枝节加载技术设计一款双模谐振器,实现双频带通滤波器设计,并将该滤波器与Wilkinson功分器进行集成,实现双频滤波功分器设计;其次,利用微带线和槽线的对偶关系,在不增加电路尺寸的基础上,引入双模槽线谐振器与微带谐振器进行垂直级联,从而展宽滤波功分器的两个通带带宽;最后利用枝节加载技术优化馈电网络。由于双模微带-槽线谐振器和馈电网络自身的特性,在每个通带的两侧分别产生一个传输零点,实现较高的带外选择性,且每个传输零点单独可控。双频滤波功分器的两个通带中心频率分别工作于2.17 GHz和3.55 GHz,相对带宽分别为8.29%(2.08～2.26 GHz)和8.15%(3.41～3.7 GHz)。仿真结果和实测结果基本吻合。     

具有高共模抑制特性的微带差分带通滤波器

该文提出了一款中心频率可调的三阶差分带通滤波器,该滤波器主要由1个折叠的枝节加载谐振器(FSLR)和1对折叠的平行耦合线结构来实现滤波特性,同时使用微带-缝隙线转换结构激励差模和抑制共模。与传统的微带滤波器相比,该结构的共模响应和差模响应无关,所以在不降低差模特性情况下实现了良好的共模抑制,使设计更灵活。该差分滤波器整体尺寸为26 mm×49.2 mm,中心频率为3 GHz,相对带宽可达28.67%,共模抑制水平优于37 dB。结果表明,实际测量结果与仿真结果基本吻合。     

低交叉极化水平的宽带滤波贴片天线

提出了一种低交叉极化水平的宽带贴片滤波天线。在层叠式贴片与金属大地之间插入一对1/4波长短路谐振器,天线的通带内可出现3个反射零点,实现了拓展天线工作带宽的效果。在通带的高端出现两个反射零点,提高了天线的高端带外抑制水平。该天线与传统的微带贴片天线相比,具有宽频带、高增益、低交叉水平以及高端频率选择性的优势。为验证理论预期的可实现性,设计了中心频率在3.5 GHz的天线案例。仿真结果表明,该天线的剖面高度为0.1λ0,10 d B匹配带宽为22%,增益为8.4 dBi,交叉极化小于-30 dB。     

应用于物联网MIMO天线的双频谐振解耦结构

提出了一种用于双频MIMO天线的谐振器去耦结构。通过双频单极子MIMO天线对该解耦结构进行验证。双频单极子天线分别工作在低频2.4GHz和高频5.8GHz。 双频解耦结构在低频段主要是采用两个反向的π型微带谐振器解耦,高频段主要是采用π型缝隙谐振器解耦。天线采用微带线馈电,解耦谐振器与天线地板印刷在PCB同一面,结构紧凑易于与系统集成,可以广泛应用于物联网通信系统中。 实测结果：双频谐振器去耦结构实现隔离度高于22dB,单极子天线阻抗带宽分别为2.0GHz-3.0GHz和5.0-6.0GHz（S11<-10dB）,低频段增益最大增益点1.5dBi,高频段最大增益点3dBi。     

374~747 MHz数字可调谐微带滤波器

通过在微带开口谐振环加载数字可调电容,设计了一种新颖数字微带可调滤波器,同时提出了新型的非均匀开口谐振环混合耦合结构,使谐振器间耦合系数随谐振频率的降低而增大,实现恒定绝对带宽可调滤波器。接着对所提出的基于5 bit数字可调电容的数字可调微带滤波器进行了仿真和制作,测试表明,其通带中心频率可实现374~747 MHz可调,?3 dB绝对带宽在44~67 MHz之间变化,OIP3大于50 dBm。     

基于半模基片集成波导馈电的Vivaldi天线设计

文章基于HMSIW(Half-mode Substrate Integrated Waveguide)结构,设计了一款Vivaldi天线。首先利用基片集成波导技术设计了一个低损耗、具有良好传输特性和带内匹配特性的SIW-微带馈电巴伦,简化了传统巴伦结构的复杂性。仿真结果显示,天线工作在7.5 18.3GHz,相对带宽为83.7%(S11<10dB),中心频率增益约为11.3dBi。天线结构紧凑、剖面低、易于集成,同时具有较宽的带宽和较好的方向特性。     

几种共面波导耦合馈电装置的特性研究

该文研究了4种共面波导耦合缝对单贴片微带天线的谐振频率以及带宽的影响,并利用天线近场分布对其进行解释;分析并比较了几种耦合缝的馈电特性,极大地提高了天线设计的灵活性;运用变频思想对馈电装置进行改进设计出了一阻抗带宽达28.9%的宽频带天线,在3.76～4.80GHz的工作频段内天线增益均大于8dBi,增益带宽达24.2%。     

超宽带阶梯形微带单极子天线的设计与研究

针对当前已有超宽带(ultra-wideband,UWB)微带单板子天线带宽窄、尺寸大等缺陷,设计了一款小型化UWB阶梯形微带单极子天线,采用开槽的矩形辐射贴片、阶梯形微带馈电线和缺陷地面结构(defected ground structure,DGS)实现良好的UWB特性.对天线的回波损耗、电压驻波比(voltage...     

Integrated design of filtering antenna with high selectivity and improved performance for L-band applications

An integrated design of compact filtering antenna having high selectivity and suppressed unwanted harmonics is proposed in this paper. The proposed filtering antenna is obtained by integrating a modified elliptic-shaped monopole antenna with a modified interdigital bandpass filter (IBPF). At first, a modified elliptic-shaped monopole antenna is designed and investigated through numerical simulation and experimentally. Further, the modified IBPF reported in the literature is integrated with the proposed monopole antenna to achieve good passband selectivity and suppressed unwanted harmonics for the proposed filtering antenna. The proposed filtering antenna is analysed through numerical simulation software. The simulated −10 dB reflection coefficient bandwidth of the proposed filtering antenna covers the frequency range 1.01–1.96 GHz with improved band-edge selectivity and unwanted harmonic suppression up to 8 GHz (= 5.4 f₀, where f₀ is the centre frequency of passband). It has nearly stable omnidirectional radiation patterns over the whole frequency band. The proposed filtering antenna was fabricated and experimentally tested. The experimental results are nearly in agreement with corresponding numerical simulation results. The proposed filtering antenna can be a suitable candidate for various L-band wireless communication applications.     

宽带高增益圆极化微带天线与阵列

设计了一副宽带高增益圆极化微带天线,并进行组阵分析。天线中心频率2.6 GHz,通过增加寄生贴片和空气层来提高天线单元的增益和带宽。上下两层介质板上边长不同的切角方形贴片分别激励一个低频与高频的圆极化模,有效地拓宽了轴比带宽。仿真结果表明,反射系数|S11|<-10 dB带宽21.8%,3 dB轴比带宽12.0%,中心频率点增益9.0 dBi。对天线单元进行加工测试,与仿真结果较为吻合。设计了2×4元阵列,并进行了仿真,增益提升至17.5 dBi,3 dB轴比带宽10.4%。     

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.     

一种宽带分形自互补单极子天线的设计

提出一种结合分形与自互补理论的新型宽带单极子天线。辐射部分由Sierpinski分形图案的金属贴片和互补的缝隙贴片印刷在FR-4 介质板上构成,由微带线经阻抗变换后馈电。分形技术的利用使得该天线实现了20%的尺寸缩减,自互补结构则大大拓展了天线的带宽,两者的结合使得该天线在保持平面结构的同时取得优良的性能。仿真与测试得到该天线在4.98-9.93 GHz 频带内反射系数小于-10dB,具有66.4%的带宽,带内增益在1.3-3.3dBi 之间。该天线具有平面、宽带、小型化的优点,在小型化通信系统中具有良好的应用前景。     

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.

     

Elliptical slot loaded partially segmented circular monopole antenna for super wideband application

This article inspects partially segmented circular monopole with elliptical slot for super wideband applications. Two significant characteristics of proposed antenna design are: (i) partially segmented circular monopole, notch loaded elliptical ground plane along with tapered microstrip line provides super wide bandwidth; (ii) elliptical slot in between the partially segmented circular monopole reduces the lower operating frequency (1.07 GHz–0.96 GHz), which in turn enhance the bandwidth dimension ratio (BDR). For verifying the simulated outcomes, antenna prototype is practically constructed and measured. The proposed antenna design attains frequency range from 0.96 GHz to 10.9 GHz (VSWR < 2) with bandwidth ratio of 11.35:1 and percentage bandwidth of 167.22%. Bandwidth dimension ratio of proposed radiator is 6975.22. Frequency as well as time domain analysis of proposed radiator approves its applicability for super wideband wireless applications.     

A compact skull‐shaped defected ground super wideband microstrip monopole antenna for short‐distance wireless communication

In this paper, a human skull‐shaped miniaturized super wideband microstrip monopole antenna is presented. The shape of the microstrip radiator is optimized and designed by combining different sizes of semicircular‐ and rectangular‐shaped radiating elements along with a microstrip feed line. On the other hand, a defected ground structure as the ground is placed at the opposite side of the radiator, which is fabricated on Rogers 5880 substrate. The electrical length of the proposed antenna is 0.240 × 0.200 × 0.016 λ at 3 GHz. The CST microwave studio is used for all the required simulations regarding antenna prototype design and optimization. The complete outcomes demonstrate that the proposed miniaturized antenna has a bandwidth of 24.5 GHz (3 to 27.5 GHz) having a radiation pattern in the form of nearly omnidirectional. The measured fractional bandwidth of the antenna is 160.66%, and the bandwidth dimension ratio is 3346.99, which is the highest among the literature review. The maximum calculated gain and efficiency are 6.3 dBi and 93%, respectively. For the time domain analysis, the antenna shows a decent performance in terms of the system group delay and fidelity factor. The numerical and experimental data are investigated throughout the study, which represents that the proposed antenna is suitable for short‐distance wireless communication like wireless local area network/Wi‐Fi/Worldwide Interoperability for Microwave Access (WiMAX)/ultra‐wideband and some other applications.