Compact Quad Band-Notched Monopole Antenna for UWB Systems

A novel compact microstrip-fed UWB antenna with quad notched band is proposed. The antenna consists of a rectangular radiating patch with a half circle, a tapered microstrip feed-line, and a semi-elliptical ground plane. With a pair of L-shaped slots, complementary co-directional SRR and a pair of C-shaped stubs, four notched bands are created to prevent interference from WiMAX/lower WLAN/higher WLAN/X-band. Experimental results show that the designed antenna, with compact size of 20 × 30 mm², has an ultrawide band (VSWR < 2) from 2.68 to 13 GHz, except four notched bands of 3.13–3.8, 4.87–5.52, 5.65–6.1, 7.12–8 GHz. Good radiation patterns and stable gain within the operating band have been observed.     

Design of Compact Quad-Band Notched UWB-MIMO Antenna

With quad-notched band characteristic, a compact ultra-wideband (UWB) multiple-input-multiple-output antenna is proposed in the article. There are two identical monopole elements in the system. By inserting symmetrical L-shaped slots, complementary split-ring resonators) and C-shaped stubs in each element, four notched bands are achieved to filter 3.5 GHz WiMAX, 5.25 GHz lower WLAN, 5.8 GHz upper WLAN, and 7.5 GHz X-band. Without decoupling structures, the antennas were placed vertically to obtain high isolation. Results indicate that the antenna operates from 2.6 to 13 GHz except four rejected bands, and port isolation (S21) is better than ?25 dB, envelope correlation coefficient is below 0.002 in UWB spectrum frequency of 3.1–10.6 GHz.     

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 NEW DESIGN METHODOLOGY FOR PRINTED LOG-PERIODIC MONOPOLE ANTENNA

In theory, Log-Periodic Antenna (LPA) is a linearly polarized antenna with frequency independent properties on the input impedance and gain patterns. Owing to these characteristics, LPA has gained research interests and been employed for many wideband applications. A Printed Log- Periodic Dipole Antenna (PLPDA) with multiple notched bands is proposed for Ultra-WideBand (UWB) applications. An antenna with the notched frequencies of 1.03 GHz, 1.28 GHz, 1.72 GHz, 2.24 GHz and 2.51 GHz is designed, fabricated, and measured. An antenna model was established on the substrate of FR4 and feed by a stripline. The simulation results show that the antenna can achieve an impendence wide bandwidth from 0.89 to 2.58 GHz with return loss less than –10 dB and exhibit stable antenna gain. Furthermore, the measurement result is better consistent with simulation result.     

Penta-notched UWB antenna with sharp frequency edge selectivity using combination of SRR,CSRR, and DGS

This work presents penta-notched UWB antenna with sharp frequency edge selectivity using combination of SRR, CSRR, and DGS to reject the WiMAX (3.30–3.60 GHz), lower WLAN (5.150–5.350 GHz), upper WLAN (5.725–5.825 GHz), downlink of X-band satellite communication (7.0–7.40 GHz), and the uplink of X-band satellite communication (8.10–8.50 GHz) frequency bands. All these frequency bands lie within the UWB frequency spectrum. The proposed antenna is suitable for portable communication applications due to its compact dimensions. It sharply notches the existing frequency bands to mitigate the interference caused by nearby wireless communication systems within UWB frequency range. The sharp notching is achieved by the combination of complementary split ring resonators (CSRR) on the radiating semi-circular patch, split ring resonators (SRR) placed at the junction of the feedline, and a pair of defected ground structures (DGS). All notched bands can be well controlled and shifted and the equivalent lumped model of the notched bands are also developed for validation. The proposed antenna simulated, and measured results show better performance over the present state-of-the-art designs. The proposed penta-notched UWB antenna possesses better reflection coefficient, VSWR, stable gain, and small foot print. The proposed antenna has a nearly omnidirectional radiation pattern in the passbands.     

基于开窗结构和寄生单元的双陷波超宽带天线

设计了一种具有双陷波特性的平面超宽带天线。超宽带基础天线的馈电采用渐变式阶梯阻抗匹配结构作,使得天线具有了宽阻抗匹配能力。通过在椭形辐射器内进行开窗,以及在地面添加矩形寄生单元,实现了天线的双陷波特性。测试结果表明,该天线的工作带宽(VSWR<2）为3.1~10 GHz,工作在超宽带(UWB)频率范围,两个陷波分别在3.3~4.0 GHz和5.0~5.85 GHz,可以应用于WiMAX和WLAN频段的信号抑制。仿真与实测结果表明,该天线结构简单、实现了良好的陷波功能,能够较好地应用于超宽带通信系统中。     

一种双阻带椭圆单极子UWB天线的设计

通过仿真与实际测试结合的方法,研究并设计了一种用于UWB通信的、具有双阻带特性的紧凑椭圆单极子天线。双阻带特性是通过在辐射单元上插入一个缝隙和在馈线上引入一共面波导谐振单元实现的。测试结果表明此天线在3.45~3.75 GHz(覆盖了WIMAX频段)和5~6 GHz(覆盖了5.15~5.85 GHz的WLAN频段)分别有两个阻带,此外,驻波系数在3.1~10.6 GHz UWB的范围内小于2。天线的辐射特性也近似于全向。天线的增益和传输函数也证实了天线能达到双阻带特性。     

一种双陷波超宽带单极子天线的设计

提出了一种新型双陷波特性的超宽带单极子天线。通过在介质基板上添加锥形辐射贴片,天线可以覆盖超宽带通信频段。在辐射贴片上引入上、下两个锥形缝隙结构,可以实现3.5 GHz、5.5 GHz的双陷波特性。天线实测模型电压驻波比＜2的阻抗带宽是2.56~10.61 GHz,其中3.18~3.76 GHz和4.4~5.75 GHz具有陷波特性。测试表明,天线在工作频带内具有全向辐射特性。     

Design of UWB monopole antenna with dual notched band characteristics by using π-shaped slot and EBG resonator

In this paper, we propose the design of coplanar waveguide (CPW) ultra-wideband (UWB) dual notched band monopole antenna with a π-shaped slot and EBG is proposed. The designed antenna produces an impedance bandwidth of 2.7–11.7 GHz (VSWR < 2), except with 3.4 GHz (3.3–3.7 GHz) for S-band WiMAX application and 6.9 GHz (6.5–7.2 GHz) for C-band IEEE INSAT applications. Here, the lower and upper notches are realized by proposing a π-shaped slot on the radiating element and an electromagnetic bandgap structure as a resonator integrated on either side of the ground plane. Meanwhile, the impedance over a frequency range and current distribution are also plotted for the proposed design. The antenna prototype is fabricated and characterized experimentally for validation purpose. Fair matching is observed among the simulated and measured results.     

Design of a Compact Hexagonal Monopole Antenna for Ultra—Wideband Applications

This paper presents two design compact hexagonal monopole antennas for ultra-wideband applications. The two antennas are fed by a single microstrip line . The Zeland IE3D version 12 is employed for analysis at the frequency band of 4 to 14 GHz which has approved as a commercial UWB band. The experimental and simulation results exhibit good agreement together for antenna 1. The proposed antenna1 is able to achieve an impedance bandwidth about 111%. The proposed antenna2 is able to achieve an impedance bandwidth about (31.58%) for lower frequency and (62.54%) for upper frequency bandwidth. A simulated frequency notched band ranging from 6.05 GHz to 7.33 GHz and a measured frequency notched band ranging from 6.22 GHz to 8.99 GHz are achieved and gives one narrow band of axial ratio (1.43%). The proposed antennas can be used in wireless ultra-wideband (UWB) communications.     

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.     

平面小型化双陷波天线设计

本文设计了一种具有双频陷波特性的小型化平面单极子天线．该天线由开有π型与W型缝隙的辐射贴片和一对L型分支组成．L型分支的作用是能够激励额外谐振,从而增加阻抗带宽,π型和W型缝隙能够实现双陷波特性．该天线可以实现超过130％的带宽（2．77～13．62 GHz）,最大的特点是具有12×18×1．6 mm3的小型化尺寸．最终的仿真和测试结果显示其在整个超宽带频段内具有良好的陷波特性、增益和全向辐射特性．     

Integrated amateur band and ultra-wide band monopole antenna with multiple band-notched

This paper presents the integrated amateur band and ultra-wide band (UWB) monopole antenna with integrated multiple band–notched characteristics. It is designed for avoiding the potential interference of frequencies 3.99 GHz (3.83 GHz–4.34 GHz), 4.86 GHz (4.48 GHz–5.63 GHz), 7.20 GHz (6.10 GHz–7.55 GHz) and 8.0 GHz (7.62 GHz–8.47 GHz) with VSWR 4.9, 11.5, 6.4 and 5.3, respectively. Equivalent parallel resonant circuits have been presented for each band-notched frequencies of the antenna. Antenna operates in amateur band 1.2 GHz (1.05 GHz–1.3 GHz) and UWB band from 3.2 GHz–13.9 GHz. Different substrates are used to verify the working of the proposed antenna. Integrated GSM band from 0.6 GHz to 1.8 GHz can also be achieved by changing the radius of the radiating patch. Antenna gain varied from 1.4 dBi to 9.8 dBi. Measured results are presented to validate the antenna performances.     

Frequency notched wide slot antenna for UWB/2.4 GHz WLAN applications

A compact frequency notched microstrip slot antenna for ultra-wideband (UWB) /2.4 GHz-band wireless local area network (WLAN) applications is proposed. The antenna is similar to a conventional microstrip slot antenna; however, by introducing a cross wide slot and a meandered-slotted stub, both compact size and frequency notched function can be achieved. It has been studied both numerically and experi- mentally for its impedance bandwidth, surface current distribution, radiation patterns, and gain. As will be seen, an operation bandwidth of over 4.61 ranging from 2.39 to 11.25 GHz for return loss lower than having a frequency notched band ranging from 4.75 to 5.85 GHz has been achieved, and good radiation performance over the entire frequency range has also been achieved.     

Band notched UWB circular monopole antenna with inductance enhanced modified mushroom EBG structures

Circular monopole antenna for ultra-wide band applications with notch band transition from WLAN to WiMAX is presented. The proposed antenna rejects WiMAX band (3.3–3.8 GHz). Antennas utilises modified mushroom-type electromagnetic band gap (EBG) structures to achieve band-notched designs. The proposed inductance enhanced modified EBG structures are 34 % compact than the conventional mushroom EBG structures. The band notched antenna designs using EBG structures have advantages like notch-frequency tuning, antenna design independent approach and omnidirectional radiation pattern. The step wise effect of inductance enhancement and tuning of notch from WLAN band (5–6 GHz) to WiMAX band is shown. Effect of variation of EBG structure parameters on which notched frequency depends is investigated. The proposed antenna has been fabricated on low cost FR4 substrate with overall dimensions as (42 × 50 × 1.6) mm³. Measured results are in good agreement with simulated ones.     

具有陷波功能的超宽带缝隙天线的设计与研究

提出了一种具有陷波功能与分形调谐支节的新型超宽带缝隙天线.该天线的结构类似于一般的微带缝隙天线,通过采用分形调谐支节引入半波长谐振结构,使得该天线不仅具备了超宽带缝隙天线的优点,还具备灵活可调的陷波功能.通过计算、测量和尺度放大实验,充分考察了天线的频域特性.实验结果表明该天线的工作频带为2.66～10.76 GHz,在4.95～5.85 GHz频段上具有陷波功能,同时具有相对稳定的辐射方向性和近似的全向特性.该研究对设计小型超宽带天线具有一定的价值.     

Frequency notched ultra-wideband microstrip slot antenna with fractal tuning stub

A frequency notched ultra-wideband (UWB) microstrip slot antenna with a fractal tuning stub is proposed. The antenna is similar to a conventional microstrip slot antenna, and by introducing a fractal tuning stub, frequency notched function is achieved. The antenna was studied experimentally regarding impedance bandwidth, radiation patterns and gain. The operation bandwidth of the antenna is from 2.66 to 10.76 GHz, in which a frequency notched band from 4.95 to 5.85 GHz was achieved, along with good radiation performance over the entire frequency range.     

Implementation and investigation of U-shaped aperture UWB antenna with dual band-notched characteristics

The design and analysis of an ultra-wideband (UWB) aperture antenna with dual band-notched characteristics are presented. The antenna consists of a circular exciting stub on the front side and a U-shaped aperture on the back ground plane. By inserting a slot and a parasitic strip to the antenna, dual notched frequency bands are achieved. A conceptual circuit model, which is based on the measured impedance of the proposed antenna, is also shown to investigate the dual band-notched characteristics. The measured impedance bandwidth defined by VSWR , 2 of 9.0 GHz (2.2?11.2 GHz), with the dual bands of 3.25?4.25 and 5.0?6.05 GHz notched, is obtained.     

Ultra Wide Band (UWB) Horseshoe Antenna for Future Cognitive Radio Applications

In this paper, an UWB micro-strip antenna design has been proposed which is suitable for future cognitive radio applications. The geometry of proposed antenna is composed of two semi-circles with their interior modified in order to achieve higher impedance bandwidth. The semi-etched ground provides further bandwidth enhancement. The proposed antenna is fabricated on an inexpensive dielectric substrate FR-4 with relative permittivity of 4.4 and thickness of 1.6 mm. The overall dimensions of UWB antenna are 60?×?60?×?1.6 mm and have a bandwidth of 5.7 GHz. The designed antenna covers the most commonly used wireless communication bands such as DCS-1800, ISM bands, GPS, Wi-MAX, WLAN, 3G, 4G, etc. The design process and the variations in antenna’s performance due to different parameters has been discussed. The design and simulation of the antenna are carried out in the Ansys Electronic Desktop HFSS. The measured results are in good agreement with simulated results and design theory which shows that the proposed antenna is good candidate for the UWB applications.

     

Design of Compact Planar Triple Band-Notch Monopole Antenna for Ultra-wideband Applications

In this article a microstrip-fed mickey shaped monopole antenna with triple notched band characteristics for ultra-wideband applications is presented. By etching two slots in the ground plane, improved VSWR bandwidth is achieved. Mickey shape radiating patch provides 10 dB return-loss bandwidth from 3.10 to 10.60 GHz. By etching three simple C-shaped slots on the radiating patch, three existing wireless communication systems which interfere with UWB band is removed which includes WiMAX IEEE802.16 (3.30–3.80 GHz), WLAN IEEE802.11a/h/j/n (5.15–5.35, 5.25–5.35, 5.47–5.725, 5.725–5.825 GHz) and X-band downlink satellite system (7.1–7.9 GHz). Experimental results reveal that the proposed antenna exhibits desirable radiation patterns in the far field, resulting omnidirectional like pattern in the H-plane and nearly dipole like pattern in the E-plane.