Triple band notched mushroom and uniplanar EBG structures based UWB MIMO/Diversity antenna with enhanced wide band isolation

Triple band-rejection MIMO/Diversity UWB antenna characteristics are described in this paper. Proposed antenna discards worldwide interoperability for microwave access WiMAX band from 3.3 to 3.6 GHz, wireless local area network WLAN band from 5 to 6 GHz and X-Band satellite downlink communication band from 7.1 to 7.9 GHz. Mushroom Electromagnetic Band Gap (EBG) structures helps to attain band notches in WiMAX and WLAN bands. Uniplanar plus shaped EBG structure is used for notch in X-band downlink satellite communication band. Decoupling strips and slotted ground plane are employed to develop the isolation among two closely spaced UWB monopoles. The individual monopoles are 90° angularly separated with stepped structure which helps to reduce mutual coupling and also contributes towards impedance matching by increasing current path length. Mutual coupling magnitude of more than 15 dB is found over whole UWB frequency range. The Envelope Correlation Coefficient is less than 0.02 over whole UWB frequency range.The variations in the notched frequency with the variations in mushroom EBG structure parameters are investigated.The antenna has been designed using FR-4 substrate and overall dimensions is (64 × 45 × 1.6) mm³.     

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.     

A compact dual band-notched UWB circular monopole antenna with parasitic resonators

A compact dual band-notched Ultra-wideband (UWB) circular monopole antenna that has two parasitic resonators in the ground plane is presented in this paper. The Inverted–U and Iron shaped parasitic resonators are located on the back side of the radiating patch to achieve the band rejection characteristics from 5 to 5.4 GHz for WLAN and 7.8 to 8.4 GHz for ITU band respectively. By cutting a rectangular slot on the ground plane, additional resonance is excited at the higher frequency band, and hence much wider impedance bandwidth can be attained. Applications of the proposed dual band-notched ultra-wideband (UWB) antenna structure with 5.2 GHz and 8.2 GHz center frequencies are demonstrated experimentally. Measured and simulated results of the magnitude of S₁₁, radiation patterns and realized gains show good agreement.     

Study of a printed circular disc monopole antenna for UWB systems

This paper presents a study of a novel monopole antenna for ultrawide-band (UWB) applications. Printed on a dielectric substrate and fed by a 50 /spl Omega/ microstrip line, a planar circular disc monopole has been demonstrated to provide an ultra wide 10 dB return loss bandwidth with satisfactory radiation properties. The parameters which affect the performance of the antenna in terms of its frequency domain characteristics are investigated. A good agreement is achieved between the simulation and the experiment. In addition, the time domain performance of the proposed antenna is also evaluated in simulations.     

改进的圆形单极子超宽带天线

为了有效地对圆形单极子超宽带天线进行小型化,在圆形贴片上进行切边和加圆处理,设计了一款尺寸为30 mm×31 mm的改进型圆形单极子天线。该天线印刷在相对介电常数为4.4、厚度为1.6 mm的FR4介质板上,通过改变切边圆和所加圆的尺寸对天线进行优化。实验结果表明,该天线在S11≤–10 d B的工作带宽为3.03~11.55GHz,相对带宽为116.9%。该天线减小了传统圆形单极子天线的尺寸,可应用于超宽带通信系统中。     

Band-notched UWB planar monopole antenna with two parasitic patches

A novel ultra-wideband antenna with band elimination characteristic is presented, which has omnidirectional patterns in the E-plane and impedance bandwidth of about 3-18 GHz with VSWR below 2. The proposed antenna is fed by microstrip line, and consists of the monopole type with two parasitism-patches rejecting 5.15-5.825 GHz bandlimited by IEEE 802.11a and HIPERLAN/2.     

一种椭圆单极子超宽带天线仿真设计

随着宽带无线通信的发展,宽带天线的研究已成为行业研究的热点,通过对多种单极天线研究,选择了平面椭圆单极子宽频天线进行了设计,并对接地板进行切角处理和各项参数分析与优化,实现了宽频天线的性能要求。与其他各种设计相比,其结构简单,制作方便。     

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.     

一种结构简单且陷波特性易调节的超宽带天线

设计了一种具有陷波特性的超宽带(UWB)天线,由一个圆环形贴片和部分地板组成,通过在贴片上 刻蚀一个弧形槽可以在不改变天线尺寸的基础上实现阻带特性。利用HFSS 仿真软件对该天线进行了仿真设计,设 计结果表明天线能够在2. 8-10. 8GHz 频带内实现宽带特性,并在5. 1-6GHz 处形成阻带。在此基础上,加工和测量 了天线模型,实测结果表明天线在工作频带内具有良好的辐射方向图和稳定的增益,而且天线尺寸小、结构简单。 非常适合应用于超宽带系统。     

一种超宽带地板开槽单极子天线的设计

研制了一款超宽带印刷单极子天线。通过在接地板和单极子贴片底部开槽,展宽了天线频带,改善了天线带内特性,提高了天线增益。采用HFSS软件进行仿真,对天线模型参数进行优化,达到最佳设计效果。结果表明,改进后的天线-10 dB阻抗带宽为2.2~14.6 GHz,比原不开槽天线的-10 dB阻抗带宽增加了7.2 GHz。天线实现了小型化超宽带的同时,在整个超宽带匹配频段内,具有良好的驻波和方向图特性,在超宽带设备中有着很好的应用前景。     

一种新型超宽带陷波天线的设计

提出了一种新型超宽带(UWB)陷波天线,该天线的结构由常规的圆形单极子天线演变而成。为获得超宽带特性,天线的辐射体被设计成渐变的笑脸形状。同时,通过在辐射贴片上开C形槽来实现陷波特性。合理选择C形槽的尺寸可有效去除超宽带频段内的无线局域网WLAN(5.150~5.825GHz)的干扰。仿真结果表明,天线在4.91~6.07GHz处形成了阻带特性(电压驻波比VSWR>2),天线结构新颖简单,适用于超宽带通信系统。     

A planar triangular monopole antenna for UWB communication

A planar triangular monopole antenna (PTMA) is presented for high-frequency structure simulator ultra-wideband (UWB) communication. The high-frequency structure simulator three-dimensional electromagnetic solver is employed for design simulation. A printed PTMA has been realized by using the FR-4 printed circuit board substrate. The measured voltage standing wave ratio is less than 3 from 4 to 10 GHz. In the UWB communication frequency range, the measured phase distribution of the input impedance is quite linear and the H-plane patterns are almost omni-directional. The Kirchhoff's surface integral representation was adopted in the developed finite-difference time-domain code to compute the far field distributions from the near filed ones in time-domain. This is to investigate the radiated power density spectrum (PDS) shaping to comply with FCC emission limit mask. The effect of various source pulses (first-order Rayleigh pulses with /spl sigma/ of 20, 30, and 50 ps) on the radiated PDS shaping is also studied.     

Band-notched inverted-cone monopole antenna for compact UWB systems

A microstrip-fed planar ultra-wideband monopole antenna with bandnotch characteristics is proposed. The antenna size is compact (18 x 30 mm) and operates over an extremely wide band of 3-16 GHz. The proposed design consists of an inverted cone as the radiating patch and a tapered ground plane. Wideband matching is obtained by properly shaping the ground. A pair of symmetrically placed quarter wave slot resonators is embedded in the ground plane for rejecting the 5-6 GHz WLAN band. Results indicate a stable and omnidirectional radiation pattern with an average gain of 3 dBi and a sharp reduction in gain at notched frequencies. Moreover, measured group delay and transmission characteristics show excellent transient response.     

A printed monopole ellipzoidal UWB antenna with four band rejection characteristics

An antenna design with four band rejection characteristics for UWB application is demonstrated. The proposed unique UWB antenna has shape of an embedded ellipse at top of trapezoidal patch (named as ellipzoidal), 50 Ω impedance microstrip line feed and a truncated beveled ground plane. To realize four band stop characteristics, three inverted U-shaped and a single I-shaped slots each of half guided wavelength are utilized on radiating element. The fabricated antenna has dimensions of 27 mm × 36 mm × 1.6 mm. This four band notched ellipzoidal UWB antenna has measured frequency bandwidth 2.8–14 GHz for magnitude of S₁₁ < −10 dB level. The measured ellipzoidal antenna exhibits four band rejection characteristics for magnitude of S₁₁ > −10 dB at 3.55 GHz for WiMAX band (3.26–3.9 GHz), 4.55 GHz for ARN band (4.35–5.05 GHz), 5.7 GHz for WLAN band (5.5–6.65 GHz) and 8.8 GHz for ITU-8 band (7.95–9.35 GHz). The proposed ellipzoidal UWB antenna maintains omnidirectional radiation pattern, gain, linear phase response, <1 ns group delay, and transfer function in the whole UWB operating bandwidth except at notched frequency bands.     

Small-size planar triangular monopole antenna for UWB WBAN applications

A novel topology, based on the PTMA, is investigated in view of UWB WBAN applications. It is shown that adding carefully placed slots in the antenna offers a lot of advantages. The study presented treats all aspects that are important. First, the specifications in the frequency domain are met for the lower UWB band. Secondly, the design is made such that a small size is obtained. Thirdly, and very important, the presence of the human body is investigated. Finally, the pulse distortion in the frequency band 4-7 GHz is investigated and found to be low. The main conclusion is that this PTMA type is a very good topology for UWB applications in combination with human bodies.     

Time domain analysis for foldable thin UWB monopole antenna

In this paper, the time domain analysis of an Ultra Wide Band antenna flexible circular monopole antenna is presented. The antenna is fabricated on liquid crystalline polymer flexible substrate with a compact geometry that makes it suitable for wearable applications under different bending conditions. The antenna is fed by coplanar waveguide transmission line and has a compact total size of 40 × 22 mm². Moreover, the antenna has good radiation efficiency (97%) over the bandwidth. The presented antenna has a good performance over the operating spectrum for straight and bending configurations. The design principals along with simulation and experimental results are presented in this contribution.     

一种改进型折叠条带带陷UWB印刷单极子天线

为满足短距离无线通信系统的要求,设计并实现了一种改进型的超宽带印刷单极子天线,通过在U型辐射臂上对称加载了两个折叠条带,使天线具备了带陷功能,利用HFSS软件详细分析了折叠条带和缝隙的尺寸变化对天线陷波特性的影响。实际制作了天线的实物,测试结果和仿真结果基本吻合。该天线的阻抗带宽可以覆盖3.04~10.95 GHz,阻带范围约为4.95~5.97 GHz,绝对带宽为7.88 GHz,完全具备超宽带性能。在整个工作频段内近似具有全向性,增益曲线平坦,天线的尺寸仅为31 mm×35 mm,结构紧凑,加工方便且容易集成。