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1.
This research has proposed a dual polarized suspended square plate rectenna for RF‐to‐DC conversion at the 2.40–2.50 GHz frequency band. The proposed dual polarized antenna yields improved isolation with an annular rectangular ring slot etched in the square radiating plate. The proposed antenna could achieve >40.00 dB isolation and >8.00 dBi gain with unidirectional radiation. The proposed SMS7630‐based rectifying circuits were measured and could realize the maximum conversion efficiency of 25.98% (1.57 V) with a 3.00 kΩ resistor and 2.00 mW input RF power of a signal generator. On integration, the experimental vertical polarization rectenna was capable of achieving the maximum conversion efficiency of 21.86% (14.20 mV) at the 0.5 m distance and 0.00015.00 mW/cm2 input power density. The proposed dual polarized rectenna can receive the input RF power density of arbitrary polarization with obtained average conversion efficiency of 14.97% (10.50 mV) at the 0.5 m distance of wireless local area network (WLAN) system. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:164–173, 2016. 相似文献
2.
A broadband dual‐polarized omnidirectional antenna is presented. The proposed antenna consists of two parts, an asymmetric biconical antenna and a cylindrical multilayer polarizer. To have an almost perfect omnidirectional radiation pattern in the horizontal plane and the main radiating beam position at around , in the elevation plane, the asymmetric biconical antenna is used. Moreover, to provide dual polarization performance over the 2–18 GHz operational bandwidth, a multilayer polarizer is designed and optimized. Numerous simulations via Ansoft HFSS and CST microwave Studio CAD tools have been made to optimize the radiation pattern, gain, polarization, and the reflection coefficient of the antenna. Simulation results show that the radiation characteristics of the proposed antenna are extremely sensitive to the configuration and dimensional parameters of the multilayer polarizer. The designed antenna was fabricated with high mechanical accuracy and measured. Satisfactory agreement of computer simulations and experimental results was obtained. The main feature that distinguishes this antenna from the previous designs is the ability to provide the omnidirectional radiation pattern with small ripples, dual polarizations performance, and the wide bandwidth simultaneously. Based on these characteristics, the proposed antenna can be useful for broadband communication applications. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:591–600, 2015. 相似文献
3.
This article presents a dual‐polarized filtering patch antenna, which uses two orthogonal modes (TE210/TE120) of the substrate integrated cavity (SIC) to couple with two orthogonal modes (TM10/TM01) of the patch by the cross slot, respectively. The second‐order filtering response on dual polarizations can be achieved by using just one SIC resonator and one slotted square patch, which display simple structure of the proposed antenna. The slotted square patch provides a new way to obtain same external quality factor of the radiator on dual polarization, which makes the performances on two polarizations agree well with each other when changing the bandwidth. High isolation can be achieved by controlling the space of the vias of the SIC. Radiation nulls can be produced by connecting the coupled lines with the feeding lines in parallel. A prototype with the entire height of 0.019 λ0 (λ0 is the free‐space wavelength at center frequency) achieves a 10‐dB bandwidth of 1.6%, the gain of 4.9 dBi at the center frequency, the port isolation of 43 dB, and the out‐of‐band rejection level of 25 dB. 相似文献
4.
Sumita Shekhawat Pratibha Sekra V. K. Saxena J. S. Saini D. Bhatnagar 《国际射频与微波计算机辅助工程杂志》2011,21(4):407-412
A novel dual‐frequency broadband design of a single‐layer single‐feed circular microstrip antenna with an off‐centered Y‐slot is demonstrated in this communication. By selecting a suitable location of the Y‐slot in the circle, the proposed antenna on glass epoxy FR‐4 substrate not only resonates efficiently at two closely spaced frequencies (2.736 and 2.868 GHz) but also offers improved bandwidth (210 MHz or 7.5%) in comparison with a conventional circular microstrip patch antenna (～2%). From the measured results, almost identical broadside radiation patterns are obtained at two resonant frequencies, and the variation of less than 1 dBi in gain values is achieved in the frequency range where broadband behavior is observed. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
5.
This article presents a high‐isolation dual‐frequency rectangular patch antenna utilizing microstrip feed line integrated with a cascade defected microstrip structure (CDMS). Two types of CDMS are added, T‐shaped CDMS and Dumbbell‐T‐shaped CDMS. Simulation results show using these structures improve isolation up to 70 dB and reduce harmonic signals from transmitter. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
6.
为增加火灾探测天线频带范围,基于微带贴片天线,采用凹槽加载技术,设计了中心频率在Ku(12.4～18.0 GHz)波段的双频微带单元天线.利用HFSS软件对其建模、仿真及优化,结果表明,该单元天线在14.8 GHz和16.1 GHz时回波损失达到最小值,且回波损失小于-10 dB的带宽分别为600MHz和390 MHz.利用该单元天线,进而设计了一款2×2阵列天线,实测结果表明:该阵列天线具有很好的双频谐振特性,在14.3～14.9 GHz和15.7 ～16.1 GHz频带内既保留了原单元天线好的回波损耗特性,又提高了增益,使两个频段最大增益分别达到13.7 dBi和11.3 dBi. 相似文献
7.
A single‐layer dual‐band circularly polarized reflectarray antenna composed by split double rings for higher band and cross dipoles for lower band is presented in this letter. By adjusting the length of the cross dipole and rotation angle of split double ring, two classes of elements achieve the required reflection phase. Then, a reflectarray with these two types of elements is fabricated and tested. It is worth noting that the designed reflectarray obtains broadband performance at both bands. Measurement results demonstrate that the fabricated reflectarray obtains a 1 dB gain bandwidth of more than 14% for both bands and a 3 dB axial ratio bandwidth of 22.9% for the lower band and 40% for the upper band. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:364–369, 2015. 相似文献
8.
A novel compact planar dual‐band multiple input multiple output (MIMO) antenna with four radiating elements for 5G mobile communication is proposed. Each radiating element has a planar folded monopole, which is surrounded by L‐shaped meta‐rim extended ground stubs. The compact folded arms act as the main radiating elements, while combined with the L‐shaped meta‐rim stubs, the proposed antenna forms multiple resonances so as to achieve dual‐band coverage. The simulated and measured results show that the proposed antenna has two wide bands of ?6 dB return loss, consisting of 1.6 to 3.6 and 4.1 to 6.1 GHz, respectively. Without any additional isolation structure between the elements, the isolation for the proposed 2 × 2 MIMO antenna in both desired bands can be achieved better than 12 dB. The measured results show that the proposed MIMO antenna with good performance, that is, stable radiation patterns, high efficiencies, low specific absorption ratio (SAR) to human tissues, is suitable for WLAN/LTE, 4G and future 5G mobile phone applications. 相似文献
9.
航天测量船在执行海上测控任务时,主要跟踪目标为C频段和S频段的航天器。受甲板面积限制,测量船无法在甲板上安装多套不同频段的天线,设计C＋S双频段共用天馈系统就显得尤为必要;在C+S频段天馈系统的硬件选择上,C频段初级辐射器采用单喇叭方式,利用TE01模、TE21模、TM01模3个差模对目标实施跟踪;S频段初级辐射器采用四喇叭方式,利用四喇叭的信号合成对目标实施跟踪;设计C+S双频段天馈系统时采用计算机辅助技术,确定了天线反射面和馈源喇叭的形式及相对关系尺寸;并通过仿真计算出天馈系统的增益、副瓣电平、差波瓣零深、差斜率等方向图关键指标均满足设计要求,达到了双频段天线的小型化和合建的目的,满足航天测量船船载设备的使用要求。 相似文献
10.
The design and development of a shared‐aperture dual‐band, dual‐polarized, dual‐aperture coupled rectangular microstrip patch antenna element is presented, which is suitable for portable very small aperture terminals. Detailed parametric studies of the locations of orthogonal coupling slots and their influences on the isolation and impedance bandwidth of the antenna element are performed. The experimental results are presented. The prototype dual‐band dual‐polarized antenna element achieves a 21% input impedance bandwidth at the S‐ and C‐bands. The design and development of a four‐element array with such an antenna element is also presented. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 180–193, 2003. 相似文献
11.
A new dual‐polarized microstrip antenna array is presented. Diagonal feeding of the square patch with two ports is proposed to obtain dual linear polarization. A novel coplanar feedline network is also presented for the dual‐polarized array. For engineering purposes, a CAD‐oriented method of analysis is developed. The measured results demonstrate high isolation between the two input ports. The array has simple structure and is easy to further combine to form larger coplanar arrays. ©1999 John Wiley & Sons, Inc. Int J RF and Microwave CAE 9: 42–48, 1999. 相似文献
12.
In this article, a crossed dipole antenna with compact size (43 × 43 mm2) and high isolation (42 dB) is proposed using a hybrid balun circuit. The hybrid balun consists of a tapered balun and a Marchand balun. The tapered balun transforms the microstrip line into the parallel feeding lines for one pair of dipoles, and the Marchand balun transforms the stripline transmission line into a couple of out‐of‐phase feeding lines for the crossed pair of dipoles. Due to the low coupling between two different baluns, a high isolation of the antenna can be achieved when the crossed dipole antenna is cascaded with the hybrid balun. Moreover, these two baluns can improve impedance matching and therefore further miniaturize the size of the crossed dipole antenna. The impedance matching of two baluns can be controlled and adjusted independently. As a result, the proposed dual‐polarized antenna has the bandwidth of 1.7 to 2.8 GHz for S11 < ?15 dB with compact size and high isolation. The proposed antenna with the hybrid balun circuit are fabricated, and the simulated and measured results meet well. 相似文献
13.
This study presents a high‐efficient, compact, and broadband microstrip patch antennas (MPAs) based on substrate‐integrated waveguide (SIW) for X‐band applications. The proposed array consists of three stacked layers from top to bottom, including one layer as the antenna layer and two SIW layers as a feeding network. The performance was focused on improving the impedance bandwidth and radiation efficiency by mitigating the loss from the feed network while also maintaining the compact design. To this end, the SIW feeding network was designed to feed the MPA to save the physical aperture size which resulted in a more compact and efficient radiating structure. The overall size of the proposed array is compact and extra surface area around the radiation aperture has not been occupied. The measured ?10 dB impedance bandwidth span is from 8.9 to 10.9 GHz (20.2%). The maximum measured gain at 10.6 GHz is 10.6 dBi. The results show that the simulated radiation efficiency and the measured aperture efficiency are more than 75% and 50%, respectively. The fabricated array exhibits great advantages such as wide operating bandwidth, lightweight, low‐cost, high aperture efficiency, high radiation efficiency, and compactness which make it a good candidate for X‐band applications. 相似文献
14.
A broadband circularly polarized patch antenna with suspended structure is proposed. The suspended patch has a bow‐tie structure and a gap‐coupled feed. By connecting a resistor load to another gap‐coupled feed port at the opposite position, a wide impedance and axial ratio (AR) bandwidths are obtained. The proposed design has a very simple antenna structure with an impedance bandwidth of 44.5% and a 3‐dB AR bandwidth of 33.8%, respectively. The results show that the bandwidth of the patch antenna is successfully broadened using the suspended configuration, gap‐coupled feed, and resistor loading. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:587–593, 2014. 相似文献
15.
A compact four and eight elements multiple‐input‐multiple‐output (MIMO) antenna designed for WLAN applications is presented in this article. The antenna operates in IEEE 802.11b/g WLAN (2.4 GHz), IEEE 802.11 ac/n WLAN (5.2 and 5.8 GHz) and WiMAX (5.8 GHz) bands. The resonated mode of the antenna is achieved by two unequal Reverse‐L shaped, line‐shaped slots on top and parasitic element on the ground layer. The single antenna provides wide bandwidth of about 29% (2.3‐3.1 GHz) in lower and 22% (4.9‐6.1 GHz) in the upper band. The compactness of the single element antenna is found about 95% with respect to the patch and 61% in overall dimension. Thereafter an investigation is carried out to design two, four, and eight elements MIMO antennas. All of the multi‐element structures provide compact configuration and cover entire WLAN frequency ranges (2.4‐2.48 and 5.15‐5.85 GHz). The dimension of the proposed eight element MIMO antenna is 102 × 52 × 1.6 mm3. It covers the frequency (measured) from 2.4 to 3.1 GHz and 5 to 6.1 GHz. The diversity performance of the proposed MIMO antenna is also assessed in terms of the envelope correlation coefficient (ECC), diversity gain (DG), and total active reflection co‐efficient (TARC). The ECC is found <0.5 whereas the DG >9.0 is obtained for the desired bands. 相似文献
16.
In this paper, a novel broadband dual‐polarization patch antenna is proposed. Antisymmetric Γ feeding network is applied to excite the radiating patch etched on the upper side of the horizontal substrate, which could minimize the undesired radiation from the probe and extend the impedance bandwidth. For verifying the proposed approach, a prototype is fabricated and measured, the simulated and measured results show the antenna has a wide impedance bandwidth of 48% (1.66‐2.71 GHz) for S11 < ?10 dB, as well as stable radiation gain around 9.5 dBi with low cross‐polarization. In addition, the total height of the antenna is only 0.17 λ0 ( λ0 is the free space wavelength of central frequency) and high port‐to‐port isolation is better than 30 dB. The characteristics of the proposed antenna illustrate it can be an indication for a micro base station in the mobile communication system. 相似文献
17.
In this paper, a dual‐polarized cross‐dipole antenna with wide beam and high isolation is designed and analyzed for base station. The proposed antenna consists of two planar cross dipoles with four square patches, two L‐shaped microstrip lines, two ground plates, four parasitic patches, and a reflector. The square patches are placed between the center of cross dipoles to couple with L‐shaped microstrip lines. By introducing the parasitic patches, the wide beam can be realized. The measured results show that the proposed antenna achieves an impedance bandwidth (|S11| < ?10 dB) of about 18.7% (1.9‐2.35 GHz) and an isolation better than 30 dB. A measured gain of 5.7 dBi and a half‐power beamwidth over 120° at the center frequency are obtained. Furthermore, the size of the proposed antenna is only 0.5λ0 × 0.5λ0 × 0.22λ0 (λ0 is wavelength at the center frequency). 相似文献
18.
Sreejith M. Nair V. A. Shameena C. M. Nijas C. K. Aanandan K. Vasudevan P. Mohanan 《国际射频与微波计算机辅助工程杂志》2012,22(5):581-587
A printed slot line fed dual‐band coplanar dipole antenna having a dimension of 0.40λg × 0.20λg suitable for both 2.4 and 5.2 GHz (IEEE 802.11 b/g and 802.11 a) WLAN application is presented. The structure comprises of a slot line fed symmetrical L strips to achieve dual‐band operation. Design equations of the antenna are developed and validated on different substrates. The simulation and experimental results show that the proposed antenna exhibits good impedance match, gain, and stable radiation patterns in both the frequency bands. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2012. 相似文献
19.
A miniaturized dual‐band C‐shaped dielectric resonator antenna (DRA) with partial ground plane is presented for IEEE 802.16d fixed WiMAX applications at 3.5 and 5.8 GHz. The design starts with dimensioning a single band cylindrical DRA, which has been transferred to get a dual‐band ring‐shaped DRA. One portion of the ring‐shaped DRA is removed for forming a C‐shaped DRA to get a more compact antenna. For easy fabrication, the compact DRA dimensioned as 60 × 50 × 6.6 mm3 is excited by a microstrip line feeding. The design parameters are inner and outer radii of the C‐shaped antenna and air gap (between DR and ground) to control both the resonating frequency and the quality factor. The result shows peak gain around 3.26 and 5.55 dBi at 3.5 and 5.8 GHz, respectively. The obtained results indicate very good agreement between the simulated and measured results. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22: 682–689, 2012. 相似文献
20.
A dual‐feed small size full‐metal‐case (FMC) antenna for hepta‐band LTE/WWAN operation in smartphone applications is presented. The antenna proposed here is an integrated part of the full metal case located at the top edge of the smartphone, and it only occupies a small volume of 5 mm × 70 mm × 6 mm. It has two feeding ports that are separately connected to an ON/OFF switch (SW1 and SW2) for controlling the lower and higher operation bands, respectively. For the case when SW1 (ON) and SW2 (OFF), Port‐1 is engaged, and a lower operating band that covers the GSM850/900 operation (824–960 MHz) is achieved. In contrast, Port‐2 will be engaged for the case when SW1 (OFF) and SW2 (ON), and with the aid of a wideband matching circuit, the antenna can induce a higher operating band that can cover the DCS/PCS/UMTS2100/LTE2300/LTE2500 operations (1690–2690 MHz). Detailed design considerations of the proposed FMC antenna are described, and both experimental and simulation results are also presented and discussed. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:595–601, 2016. 相似文献