共查询到20条相似文献,搜索用时 250 毫秒
1.
Latif S.I. Shafai L. Sharma S.K. 《Antennas and Propagation, IEEE Transactions on》2005,53(3):994-1003
Reduced size microstrip monopole slot antennas with different slot shapes-straight, L and inverted T, and placed on a small ground plane, are investigated. The ground plane size is 50 mm/spl times/80 mm, which is about the size of a typical PC Wireless card. Detailed simulation and experimental investigations are conducted to understand their behavior and optimize for broadband operation. It is shown that, the variation in the slot shape, from straight to L and T shapes, helps in generating additional resonances, which when coupled to the original resonances of the slot, further increases impedance bandwidths. The bent shapes of the L and T slots reduce their height and provide more space on the ground plane for electronics. A mirror image dual L-slot antenna, placed at two adjacent corners of the ground plane, is also investigated and optimized for the polarization diversity. They provide an impedance bandwidth of 87%, with near orthogonal radiation characteristics. The measured impedance bandwidths (S/sub 11/=-10 dB) of up to 60%, 84%, and 80% are achieved for these straight, L and inverted T slots respectively, by suitably selecting their design parameters. The simulation results are in good agreement with the experimental data considering several practical issues. 相似文献
2.
A folded slot is introduced to expand the impedance bandwidth and miniaturise the size of a coplanar waveguide (CPW)-fed patch monopole antenna for radio frequency identification (RFID) applications. The designed antenna, which, including ground plane, is only 13 mm in height and 11 mm in width, can operate at the 5.8 GHz band with measured impedance bandwidth and average antenna gain of 30% and /spl ges/5 dBi, respectively, and also conical radiation patterns. These properties make the antenna suitable for RFID tags. 相似文献
3.
The design of an aperture-coupled annular-ring microstrip antenna for circular polarization (CP) is presented. The CP radiation of the annular-ring microstrip antenna is achieved by a series microstrip-line-feed configuration through the coupling of a ring slot in the ground plane. The key parameters of the proposed design are investigated using a commercial simulation software based on the Method of Moments to show how to obtain the 50 /spl Omega/ input impedance and optimum axial ratio. The proposed design can be applied to the annular-ring microstrip antennas with different inner radii and substrate thickness, and several antenna prototypes are constructed and measured. Details of the experimental results of the CP performance are presented and discussed. 相似文献
4.
《Antennas and Propagation, IEEE Transactions on》2009,57(5):1353-1359
5.
An ultra-wideband slot antenna realised in low-temperature cofired ceramic (LTCC) technology is reported. The antenna is developed for a single-package solution of ultra-wideband radio. The radiating element of the antenna has a shape of ellipse 11 mm wide and 17 mm long. It shares the ground plane with other radio circuitry and is fed through a microstrip line 41 mm long and 3 mm wide. The experimental result shows that the prototype antenna achieved a bandwidth of 7.6 GHz (return loss S11/spl les/-10 dB or VSWR 2:1 from 3 to 10.6 GHz). The antenna radiation patterns at 3.5, 6.85 and 10.1 GHz are also presented. 相似文献
6.
本文提出了一种基于双圆环缝隙结构的超宽带微带天线。天线的底层由接地面的2个圆环缝隙组成,圆环之间用
2条矩形切口连接,以增加环缝之间的耦合。通过改变缝隙的位置、大小及矩形切口的位置来实现超宽带。顶层由50 ? 开
路微带线耦合馈电,通过在传输线加载匹配枝节实现更好的阻抗匹配。天线大小为40mm?40mm,厚度为1.5mm。通过
仿真表明,该天线在2.98G-9.45G频带内S11参数小于-10dB,达到3.17倍频,满足超宽带天线的要求 。最后根据仿真参数
将天线加工成实物,测试结果与仿真结果吻合。 相似文献
7.
A small microstrip patch/slot antenna, which achieves a very large bandwidth on a relatively thin substrate (about 0.01lambda0), is presented. The performance is achieved by employing a combination of annular-ring loading on the patch radiator and the use of a crossed-slot for miniaturisation. An additional ring-slot in the ground plane is used to produce the wideband characteristics of the antenna. Simulated and measured results indicate that a 53% fractional impedance bandwidth is achieved with respect to the centre frequency of 1.409 GHz and the size of the antenna is reduced by 50% compared to the conventional circular patch antenna with respect to a given frequency 相似文献
8.
9.
A novel and compact ultra-wideband printed antenna with band-rejection characteristic is proposed. By cutting an L-shaped notch on the radiating patch, the impedance bandwidth of the proposed antenna can be enhanced. In addition, a C-shaped slot is introduced to obtain the band-rejection operation of the antenna. The antenna, with compact size of 15.5/spl times/21 mm including the ground plane, operates over 3.08-10.97 GHz and has the rejected band from 5.03 to 5.91 GHz. 相似文献
10.
With the virtual enforcement of the required boundary condition (BC) at the end of a slot antenna, the area occupied by the resonant antenna can be reduced. To achieve the required virtual BC, the two short circuits at the end of the resonant slot are replaced by some reactive BC, including inductive or capacitive loadings. The application of these loads is shown to reduce the size of the resonant slot antenna for a given resonant frequency without imposing any stringent condition on the impedance matching of the antenna. A procedure for designing this class of slot antennas for any arbitrary size is presented. The procedure is based on an equivalent circuit model for the antenna and its feed structure. The corresponding equivalent circuit parameters are extracted using a full-wave forward model in conjunction with a genetic algorithm optimizer. These parameters are employed to find a proper matching network so that a perfect match to a 50 /spl Omega/ line is obtained. For a prototype slot antenna with approximate dimensions of 0.05/spl lambda//sub 0//spl times/0.05/spl lambda//sub 0/ the impedance match is obtained, with a fairly high gain of -3dBi, for a very small ground plane (/spl ap/0.20/spl lambda//sub 0/). Since there are neither polarization nor mismatch losses, the antenna efficiency is limited only by the dielectric and ohmic losses. 相似文献
11.
This paper presents a bandwidth enhanced, compact planar ultra-wideband antenna design for wireless personal area communication (WPAN) applications. The proposed antenna has fractal based geometry and is constructed using several iterations of a pentagon slot inside a circular metallic structure. The partial ground plane of the basic radiator is tapered, defected and a U slit is etched out from the microstrip feed to improve the −10 dB |S11| bandwidth. The proposed fractal based antenna has an impedance bandwidth from 2.9 GHz to 15 GHz with low profile configuration and is fabricated on FR4 substrate with dimensions of 32 mm × 32 mm × 1.6 mm. To authenticate the designed prototype, the antenna is fabricated and tested for impedance and radiation characteristics. The designed antenna has stable radiation characteristics in the operating band. Furthermore, the antenna is validated for its applicability in WPAN, by calculating fidelity factor through time domain analysis along with the transmission coefficient and group delay measurements. 相似文献
12.
Elliptical planar monopole antenna with extremely wide bandwidth 总被引:2,自引:0,他引:2
A planar monopole antenna with an extremely wide bandwidth is introduced, which is composed of an elliptical monopole patch and a trapeziform ground plane, both printed on the same side of a substrate, and is fed by a tapered CPW feeder in the middle of the ground plane. The simulated and experimental results demonstrate that this antenna achieves a ratio impedance bandwidth of 21.6:1 for VSWR/spl les/2, and exhibits a nearly omnidirectional radiation pattern, while its area is only about 0.19/spl lambda//sub l//spl times/0.16/spl lambda//sub l/ where /spl lambda//sub l/ is the wavelength of the lowest operating frequency. 相似文献
13.
14.
Surajit Mukherjee Avisankar Roy Smarajit Maity Tapas Tewary Koushik Dutta Sunandan Bhunia 《International Journal of Communication Systems》2023,36(15):e5565
An electromagnetic band gap (EBG) coupled miniaturized tri-notched printed ultra-wideband (UWB) monopole microstrip antenna having dimensions of 22 mm × 26 mm × 1.6 mm loaded with a slot in radiating patch and a parasitic strip in the ground plane has been presented. The proposed structure incorporates a square-shaped metallic radiating patch with a square EBG structure adjacent to the microstrip feed line, a U-shaped meandered slot over the radiating element, and a U-shaped parasitic resonator at the ground plane beneath the radiating element, to reject the C-band satellite downlink (3.7 to 4.2 GHz), WLAN frequency band (5.15 to 5.85 GHz), and X-band satellite downlink (7.25 to 7.75 GHz) frequency bands, respectively. The designed antenna operates in the frequency range from 3 to 11.1 GHz, with an impedance bandwidth of 8.1 GHz and a percentage bandwidth of 114%. Modification steps incorporating into the reference antenna to achieve the desired design objectives have been discussed, along with parametric studies. The proposed design has been simulated using Ansys HFSS, and measurement has been taken using standard measurement technique and compared with the simulated results. 相似文献
15.
Rezaul Azim Mohammad Tariqul Islam Norbahiah Misran 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(8):969-978
A compact planar antenna operating at a frequency range of 3–16 GHz is presented for wideband applications. The antenna is
composed of a square patch fed by a microstrip line and a partial ground plane with a rectangular slot. The proposed antenna
is very easy to be integrated with microwave circuitry for low manufacturing cost. The flat antenna has a compact structure
and the total size is 29 mm × 22 mm. The result shows that the measured impedance bandwidth (VSWR≤ 2) of the proposed antenna
is 3.2–15.44 GHz, with a notch from 4.7 to 5.8 GHz. The effects of the structure parameters on impedance bandwidth are also
investigated. Details of the proposed compact planar antenna design are presented and discussed. 相似文献
16.
提出了一种单对角线开缝的方形单元构成的透射型极化旋转超表面,并将其应用于宽带圆极化微带缝隙天线的设计中。采用等效电路法分析了超表面实现线-圆极化转换的工作机制,并对天线圆极化带宽的影响因素进行了参数扫描。仿真结果表明:加载超表面使线极化微带缝隙天线产生了圆极化辐射;同时,扩展了天线的阻抗带宽。天线相对阻抗带宽达到了33.2%,3 dB轴比带宽达到了19.5%,在阻抗带宽内天线增益均高于6.8 dBi,证实了新型超表面结构具有良好的极化旋转特性。 相似文献
17.
A modified fork-shaped microstrip monopole antenna with the ground plane including a dual-triangle portion is studied experimentally to obtain a large bandwidth and a multi-band characteristic. In this case, the ground plane including a dual-triangle portion leads to improving the impedance matching for a lower band. Although the use of a high relative permittivity (/spl epsiv//sub r/=4.3) substrate usually restricts the operation bandwidth, the radiation resistance also was a low value. The 2.0 VSWR impedance bandwidth is 29.8% (731-987 MHz) for a lower band, and 90.2% (1498-3080 MHz) for a higher band operation. This single-layer microstrip monopole antenna also retains a low and a thin profile characteristic. 相似文献
18.
A microstrip antenna with broadband circular polarisation (CP) is presented. The proposed microstrip antenna has a circular patch and is excited by a series microstrip-line-feed configuration through the coupling of a ring slot in the ground plane. The broadband operation is achieved by coupling two CP resonant elements, which are due to the circular patch and the ring slot, respectively. A typical prototype using foam material of thickness 5 mm as the antenna substrate is constructed. Measured results show the 3 dB-axial-ratio bandwidth centred at 2500 MHz is more than 10%. 相似文献
19.
A compact microstrip fed dual polarised multiband antenna for IEEE 802.11 a/b/g/n/ac/ax applications
A compact microstrip fed dual polarised multiband monopole antenna for IEEE 802.11 a/b/g/n/ac/ax communication based applications is presented. The antenna is circularly polarised in IEEE 802.11 b/g bands while linearly polarised in IEEE 802.11 a/n/ac/ax bands. The asymmetric U-shaped slot in the ground plane of proposed antenna is used to introduce the necessary 90° phase shift between two orthogonal electric field vectors necessary for circular polarisation. The Ω-shaped slot on patch is used to introduce a band elimination notch between the usable frequency bands. The radiation characteristics of the proposed antenna (at 2.4 GHz) can be changed from left hand circular polarisation (LHCP) to right hand circular polarisation (RHCP) by replacing asymmetric U-shaped slot with its mirror image on the opposite side of ground plane. The proposed antenna has a wide impedance bandwidth of 110.8% and can also be used in various applications including worldwide interoperability for microwave access (WiMAX) and IEEE 802.11p standard based V2V (Vehicle to Vehicle) communication. 相似文献
20.
In this letter, a novel hybrid planar inverted‐F antenna (PIFA) with a T‐shaped slot on the ground plane is proposed. The loop structure formed by the feed line and shorting pin can be operated as a series and shunt inductance for the PIFA and the T‐shaped slot antenna, respectively. The PIFA operates at a frequency of 1.75 GHz, while the T‐shaped slot on the ground plane operates at 2.4 GHz by the same voltage feeding source. The height of the PIFA is 6.5 mm, and the size of an upper patch is designed to be 30 mm…16 mm. The measured relative impedance bandwidth of the PIFA and the T‐shaped slot are about 12% and 21%, respectively. In addition, good antenna performance was achieved. 相似文献