Design and Analysis of Triple-Band Rectangular Microstrip Antenna Loaded with Notches and Slots for Wireless Applications

In this paper, a rectangular triple-band microstrip antenna has been designed for Bluetooth application by successively loading notches and slots of different dimension in radiating patch. The conventional microstrip antenna suffers with narrow impedance bandwidth. The current work affords an alternate option to enhance the bandwidth of antenna that resonates in triple-band operation. Initially, the antenna is resonating in single-band but after loading slots, the bandwidth of microstrip antenna has been obtained 1.97% (lower band), 10.35% (middle band) and 33.16% (upper band) resonating in triple-band with three resonant frequency at 1.422 GHz (lower resonant frequency), 1.791 GHz (middle resonant frequency) and 2.467 GHz (higher resonant frequency). The suggested antenna has upper frequency band in the range of 2.045–2.858 GHz resonating at 2.467 GHz frequency and it is appropriate for Bluetooth applications (2.40–2.48 GHz) and both lower band useful for other wireless (L-band) applications. The return loss of upper band is ??34.52 dB at 2.467 GHz. The suggested microstrip antenna is directly fed by 50 ohm microstrip line feed. The suggested antenna has been designed, simulated and analyzed by IE3D simulation software.

     

Ultra-Wideband L-Strip Proximity Coupled Slot Loaded Circular Microstrip Antenna for Modern Communication Systems

An analysis and design of a novel ultra wideband L-strip proximity coupled slot loaded circular microstrip antenna is proposed. The theoretical model is developed using circuit theoretic approach and obtained results are validated by MoM based IE3D simulation software. Theoretical results show a good agreement with simulated results. The patch is designed on a thick substrate of thickness 11 mm for a design frequency of 3.74 GHz and provides ultra wide band operation. The parametric study is carried out for return loss, radiation pattern, antenna efficiency, radiation efficiency and gain. It is observed that the bandwidth of the antenna depends on slot parameter and L-strip feed dimensions. An ultra bandwidth of 2.82 GHz is achieved with consistent radiation characteristics.     

Frequency Tunable Microstrip Patch Antenna Using RF MEMS Technology

A novel reconfigurable microstrip patch antenna is presented that is monolithically integrated with RF microelectromechanical systems (MEMS) capacitors for tuning the resonant frequency. Reconfigurability of the operating frequency of the microstrip patch antenna is achieved by loading it with a coplanar waveguide (CPW) stub on which variable MEMS capacitors are placed periodically. MEMS capacitors are implemented with surface micromachining technology, where a 1-mum thick aluminum structural layer is placed on a glass substrate with a capacitive gap of 1.5 mum. MEMS capacitors are electrostatically actuated with a low tuning voltage in the range of 0-11.9 V. The antenna resonant frequency can continuously be shifted from 16.05 GHz down to 15.75 GHz as the actuation voltage is increased from 0 to 11.9 V. These measurement results are in good agreement with the simulation results obtained with Ansoft HFSS. The radiation pattern is not affected from the bias voltage. This is the first monolithic frequency tunable microstrip patch antenna where a CPW stub loaded with MEMS capacitors is used as a variable load operating at low dc voltages     

Circuit Theory Analysis of Aperture Coupled Patch Antenna for Wireless Communication

An analysis of dual band aperture coupled microstrip patch antenna is performed using modal expansion cavity model. The theoretical investigation of antenna characteristics such as return loss, VSWR and radiation pattern is represented. The influence of geometric parameters of the aperture coupled microstrip patch antenna, such as aperture length and width, height of the substrate, dielectric constant are also investigated. It is found that antenna resonates at two distinct modes i.e. 4.39 and 5.55 GHz for lower and upper resonance frequencies respectively. The bandwidth of the aperture coupled microstrip patch antenna at lower resonance frequency is 10.23% (theoretical) and 13.33% (simulated) whereas at upper resonance frequency, it is 5.69% (theoretical) and 3.59% (simulated). The frequency ratio obtained for upper to lower resonance frequencies for theoretical and simulated results are 1.5 and 1.37 respectively. The theoretical results are compared with IE3D simulation results along with reported experimental results and they are in close agreement.     

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.     

带金属柱矩形贴片天线的谐振频率

首次采用有限元与谐振腔模型结构的混合有限元方法对有金属方柱的薄基片矩形贴片天线的谐振频率进行了数值计算和实验分析，谐振频率的计算结果与实验结果符合很好。     

Analysis of a new compact microstrip antenna

A new compact microstrip antenna element is analyzed. The analysis can accurately predict the resonant frequency, input impedance, and radiation patterns. The predicted results are compared with experimental results and excellent agreement is observed. These antenna elements are more suitable in applications where limited antenna real estate is available     

Analysis of F-shape microstrip line fed dualband antenna for WLAN applications

An analysis of microstrip line fed antennas has been presented theoretically using circuit theory concept. The theoretical investigations of F-shape antenna parameters such as return loss, VSWR, gain and efficiency have been calculated. It is found that antenna resonate at 2.4 and 5.2 GHz for lower and upper resonance frequencies respectively. The bandwidth of the F-shape antenna at lower resonance frequency is 20.08 % (simulated) and 17.05 % (theoretical) whereas at upper resonance frequency, it is 5.93 % (simulated) and 5.78 % (theoretical). The characteristics of the F-shape antenna is compared with other microstrip line fed antennas. It is found that F-shape antenna is linearly polarised along the X direction. The theoretical results are compared with IE3D simulation results as well as reported experimental results and they are in close agreement.     

A novel 5.8 GHz quasi-lumped element resonator antenna

In this paper, a novel quasi-lumped element resonator antenna is presented. The proposed antenna consists of the interdigital capacitor in parallel with a straight line inductor and is fabricated on Duroid RC4003C circuit board. The entire arrangement was fed by a coaxial feed at a frequency of 5.8 GHz. The size, bandwidth and radiation patterns were studied. The proposed antenna exhibits better impedance bandwidth and significant size reduction in comparison with similar results obtained from the conventional microstrip patch antenna with similar feeding technique and resonant frequency. The size of the proposed antenna structure is 5.8 × 5.6 mm² and experimental results are shown to be in good agreement with the design simulation.     

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.     

基于高阻抗表面PBG结构微带天线的设计与分析

以高介电常数介质为基底,利用辐射贴片开槽和微带馈电技术,设计了一款尺寸仅为16mm×12.45mm的小型微带天线。通过在此天线微带贴片周围加载高阻抗表面型光子晶体,有效抑制了表面波,改善了以高介电常数介质为基底的贴片天线的性能,实现了一款多频小型化PBG天线。HFSS仿真结果表明,加载高阻抗表面结构后的微带天线出现了三个谐振频点,分别为2.74、2.86和3.80GHz,其对应的增益分别达到6.02、8.38和5.69dB。所设计的光子晶体天线物理尺寸较小,方向性良好且具有多频特性,因此可为实际通信天线的应用提供参考。     

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.     

Microstrip-Franklin Antenna

Phasing stubs are employed to achieve a cophase current distribution in microstrip rectangular patch arrays. This technique, originally proposed for resonant long wire antennas by Franklin, avoids spurious radiation from half-wavelength connecting transmission lines as used in conventional patch antenna arrays. A slot-radiator model is derived to describe the basic radiation mechanism of the resultant new type of antenna and experimental results for the slot radiation resistance are given. The design of a 13-element resonant array for 12 GHz is presented together with measured radiation patterns.     

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.     

Compact notch loaded half disk patch antenna for dualband operation

In this article, microstrip patch antenna loaded with two symmetrical vertical notches and shorting pin is investigated for dualband operation using circuit theory concept based on modal expansion cavity model. It is found that the antenna resonates at 2.84 and 6.33 GHz for upper and lower resonance frequencies respectively. The bandwidth of the compact notch loaded antenna at lower resonance frequency is 9.94 % (theoretical) and 6.67 % (simulated) whereas at upper resonance frequency, it is 12.99 % (theoretical) and 11.59 % (simulated). The compact notch loaded antenna characteristics are compared with other proposed radiating structures. The theoretical results are compared with IE3D simulation as well as reported experimental results and they are in close agreement.     

Novel radiation pattern reconfigurable antenna with six beam choices

This article presents a novel radiation pattern reconfigurable antenna with six beam choices,which works in 5.2 GHz wireless local area network (WLAN) frequency band.The designed antenna has good imped...     

Dual-band toroidal beam antenna for WLAN communications

A novel dual-band toroidal beam antenna for wireless local area network (WLAN) communications is presented. The antenna mainly consists of six dual-band inverted-L radiating elements and a twosection six-way microstrip power divider. By inserting slots into the radiating elements, two resonant frequencies are achieved at WLAN bands. By using the two-section six-way power divider, the six radiating elements are excited with equal amplitude and phase at the two working frequency bands. A prototype has been constructed and tested. Good toroidal beam radiation patterns for 2.4 and 5.2 GHz bands are obtained.     

基于HFSS的无线传感器网络节点微带天线设计与仿真

根据微带天线的辐射原理,设计一种谐振频率为2.47 GHz的矩形微带天线,并对微带天线频带的展宽方法进行了研究。通过附加贴片来修改等效谐振电路,使其具有多个谐振点,从而扩展阻抗带宽,仿真结果表明该天线的阻抗带宽达到了12%(300 MHz)。该天线具有体积小、宽频带和低抛面等特点,可作为无线传感网络节点的终端天线,具有一定的工程应用价值。     

基于BP神经网络的分形DGS微带天线设计

微带天线易于产生谐波辐射,造成功率的损耗。加入DGS的微带天线可以抑制谐波,但是普通DGS会增加天线的背向功率漏射,且接地板利用率较低,分形DGS可以很好地克服这些缺点。为了缩短DGS的设计周期,采用BP神经网络对DGS进行进建模,在此基础上分析设计了一种分形DGS微带天线,并对制作的实物进行了测量,测量结果与仿真结果吻合较好,证明了该神经网络模型的正确性和分形DGS在微带天线谐波抑制中的有效性。     

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.