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1.
提出了一款应用于超高频段(Ultra High Frequency,UHF)(912 ~935 MHz)的射频识别(RFID)读写器圆极化单层结构微带天线,基板采用FR4 板材达到价格低廉、辐射贴片采用开槽的结构实现小型化、接地板采用开槽结构提高天线的增益,该天线实现了小型化设计,满足了天线的设计要求。利用三维电磁仿真软件对天线模型进行了分析,仿真与测试结果吻合良好。天线测试结果表明:回波损耗小于-10 dB 的阻抗带宽为25 Hz(910 ~ 935 MHz),轴比(AR)小于3 dB的带宽为21 MHz(914 ~935 MHz);在UHF 频段内,读写器天线的最大增益为-1.2 dB,所以本天线能满足我国射频识别读写器的应用要求,具有良好的应用前景。 相似文献
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A novel antenna design method for controlling resonance frequencies is presented. This method can be realised by simply inserting a spiral inductance and a gap capacitance into a conventional loop-type antenna, and this technique remarkably enhances an impedance bandwidth without increasing the antenna size. The proposed antenna has been designed to have 530 MHz (975?1505 MHz) and 150 MHz (2410?2560 MHz) dual bands (VSWR = 2.5), and can be effectively used as an internal antenna for global system for mobile communications (GSM) and Bluetooth bands. These wideband characteristics provide a critical advantage because the shift of an antenna operation frequency increases when it is near various other components. 相似文献
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提出一种适合在全面屏手机终端上使用,带宽为700~960 MHz、1 710~2 170 MHz、2 500~2 700 MHz的手机天线.设计的手机仿真模型的长宽高尺寸为158 mm×77 mm×7.5 mm,手机天线的长宽高尺寸为70 mm×5 mm×4 mm,其天线效率分别为20%~35%(700~960 MHz)、20%~55%(1 710~2 170 MHz)、25%~35%(2.5~2.7 GHz).在目前全面屏天线净空区域3.5 mm的情况下,天线的辐射效率能够满足设计要求. 相似文献
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Ali M. Hayes G.J. Huan-Sheng Hwang Sadler R.A. 《Antennas and Propagation, IEEE Transactions on》2003,51(7):1452-1461
A multiband internal antenna is introduced. The antenna consists of a driven meander-line element and two parasitic elements. The design is particularly unique since it supports the third generation mobile phone handsets where multiband operation is greatly desired. The proposed antenna operates effectively in the AMPS 800 (824-894 MHz), GSM 900 (880-960 MHz), and GSM 1900 (1850-1990 MHz) bands within 2.5:1 voltage standing wave ratio (VSWR). Detail design criteria with respect to geometrical parameter variation are given. Experimental data (VSWR and pattern) obtained from a laboratory prototype are also presented. 相似文献
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在分析电小天线理论的基础上,设计了一款适用于船载通信的短波鞭状天线。天线体高度为2 m,内径为100 mm,利用HFSS电磁仿真软件建立了仿真模型。通过电抗加载来改善天线低频段阻抗特性,并在天线馈电端进行匹配网络设计,使天线在5 MHz~15 MHz频段内阻抗平稳,有效增加了带宽;通过天线结构的改进,有效提高了天线效率,增益达到-15 dB(5 MHz~9 MHz)和-10 dB(9 MHz~15 MHz),电压驻波比小于1.8,交叉带宽大于500 KHz。并且其结构紧凑,体积小,抗风能力强,符合船载环境下天线的设计需求。 相似文献
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Triple-frequency planar monopole antenna for side-feed communication device on GSM/DCS/PCS operation
A novel side-feed planar monopole antenna capable of triple-frequency operation at about 900, 1800 and 1900 MHz is presented. The planar monopole antenna occupies a small area of 6/spl times/31 mm, and is easily made using thin copper. The planar monopole antenna can be side-fed and mounted perpendicularly to the main circuit board of a communication device so that it offers a novel design with a free degree of feed point so as to save device space, resulting in a low profile to the system ground plane. In addition, the obtained impedance bandwidths of the proposed antenna at about 900, 1800 and 1900 MHz can cover the GSM (890-960 MHz), DCS (1710-1880 MHz) and PCS (1850-1990 MHz) bands. 相似文献
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设计一种双频宽带多输入多输出(MIMO)天线。天线采用微带线耦合馈电,在天线的表面开有圆环形缝隙,把宽缝隙和窄缝隙结合到一起,因此在辐射体上同时存在2种缝隙结构;天线采用双面结构,带宽范围为1.7~2.33 GHz和3.2~3.9 GHz,2个频带的带宽分别为630 MHz和700 MHz,可用于移动通信的DCS(1 710~1 880 MHz)、PCS(1 850~1 990 MHz)、UMTS(1 920~2 170 MHz)以及WIMAX(3.3~3.6 GHz)。天线在低频段的最大增益为3.6 dB,在高频段的最大增益为5.1 dB,隔离度在-20 dB以下,符合MIMO天线的设计需求。 相似文献
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为手机天线设计了一种新颖的频率可调电路,这种设计考虑到影响手机天线设计的几个因素,例如电子开关的偏置的局限和非线性失真.设计和测试了一款能够在850MHz/1800MHz和900MHz/1900MHz之间切换的四频手机天线.天线装配在一块与手机PCB物理尺寸相当的一块印制电路上.调节的电路包括低通滤波器、隔直电容和一只Pin Diode开关.最终设计的天线在两个频带内具有较高的辐射效率和较低的非线性失真. 相似文献
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For this study, we designed an implantable rectangular spiral antenna for medical biotelemetry in the Medical Implant Communications Service band (402 MHz to 405 MHz). The designed antenna has a U‐shaped loop for impedance matching. The antenna impedance is easily adjusted by controlling the shape and length of the U‐shaped loop. Significant design parameters were studied to understand their effects on the antenna performance. To verify the potential of the antenna for the desired applications, we fabricated a prototype and measured its performance in terms of the resonant characteristics and gain radiation patterns of the antenna. In the testing phase, the prototype antenna was embedded in human skin tissue–emulating gel, which was developed to simulate a real operation environment. The measured resonant characteristics show good agreement with the simulations, and the ?10 dB frequency band is within the range of 398 MHz to 420 MHz. The antenna exhibits a maximum gain of ?22.26 dBi and an antenna efficiency of 0.215%. 相似文献
11.
Paulides MM Bakker JF Chavannes N Van Rhoon GC 《IEEE transactions on bio-medical engineering》2007,54(11):2057-2063
In this paper, we describe a specifically designed patch antenna that can be used as the basis antenna element of a clinical phased-array head and neck hyperthermia applicator. Using electromagnetic simulations we optimized the dimensions of a probe-fed patch antenna design for operation at 433 MHz. By several optimization steps we could converge to a theoretical reflection of -38 dB and a bandwidth (-15 dB) of 20 MHz (4.6%). Theoretically, the electrical performance of the antenna was satisfactory over a temperature range of 15 degrees C-35 degrees C, and stable for patient-antenna distances to as low as 4 cm. In an experimental cylindrical setup using six elements of the final patch design, we measured the impedance characteristics of the antenna 1) to establish its performance in the applicator and 2) to validate the simulations. For this experimental setup we simulated and measured comparable values: -21 dB reflection at 433 MHz and a bandwidth of 18.5 MHz. On the basis of this study, we anticipate good central interference of the fields of multiple antennas and conclude that this patch antenna design is very suitable for the clinical antenna array. In future research we will verify the electrical performance in a prototype applicator. 相似文献
12.
提出了一种工作在VHF/UHF频段的双频段宽带垂直极化车载鞭状天线。天线在VHF中馈车载鞭状天线的下辐射体顶端加一个UHF频段8λ40 MHz/4同轴扼流套,将上辐射体分为三段并在段间串接两个λ840 MHz/2倒相线圈,在天线底部加同轴扼流圈,完成了一种VHF中馈鞭状天线与一副UHF三元串联馈电直线阵天线复合的新型VHF/UHF双频段超宽频带垂直极化车载全向天线。该天线在VHF频段(30 MHz~225 MHz),UHF频段(800 MHz~880 MHz)内均具有良好的辐射特性。增益在VHF频段为1.5~4.5 dB i,在UHF频段大于6 dB i。 相似文献
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面向超高频(UHF)通用型射频识别(RFID)读写器天线的应用需求,设计了一款完全覆盖全球UHF(840-960MHz)频段的RFID圆极化读写器天线。天线采用平面缝隙贴片结构,以共面波导(CPW)馈电方式实现宽频带圆极化特性。测试结果表明,天线的阻抗带宽为735-1014MHz(S11<-10dB),相对带宽31.9%,并且在840-960MHz频段内S11<-20dB,3dB轴比带宽为838-1134MHz,相对带宽30.0%,工作频带内有大于3.5dBi的平坦增益。仿真结果与测试结果基本吻合,天线结构精简,易于加工,满足全球UHF RFID读写器天线的应用需求。 相似文献
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The design and experimental results of a very wideband small printed dipole antenna array are presented. The impedance bandwidth (VSWR ⩽1.7) of the antenna, centred at 780 MHz, is 47%. In the frequency band 610-960 MHz, the designed antenna has a gain of 9.5-11.9 dBi, sidelobe level <-16 dB and front-to-back ratio <30 dB. The main features of the design are the use of parasitic elements to expand the frequency band and the application of a mesh frame to decrease the sidelobe level 相似文献
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《Electronics letters》2008,44(25):1448-1450
A novel asymmetric fork-like monopole antenna for digital video broadcasting-terrestrial (DVB-T) signal reception for application in the UHF band is presented. The proposed antenna consists of two two-branch strip monopoles on a rectangular ground plane with a concave. The concavity in the ground pattern serves as an effective means for the gap between the radiating element and the ground plane for impedance matching. The influence of various parameters on antenna characteristics has been investigated. Results show a wide bandwidth of 461 MHz (451?912 MHz) or 70% of DVB-T centred frequency (655 MHz). The proposed antenna has omnidirectional radiation patterns in the yz-plane. Details of the proposed antenna design and experimental results of the constructed prototypes are presented. 相似文献
20.
Taeyoung Yang William A. Davis Warren L. Stutzman S. M. Shajedul Hasan Randall Nealy Carl B. Dietrich Jeff H. Reed 《Analog Integrated Circuits and Signal Processing》2011,69(2-3):161-171
Antennas are a key enabling technology for software-defined radio (SDR). Although software is extremely flexible, SDR??s potential is limited by antenna size and performance. In this paper, we review typical antenna miniaturization techniques and fundamental theories that limit antenna size and performance including operational bandwidth, gain (or range), and radiation pattern. Possible antenna design strategies are discussed to meet the desired specifications in SDR based on observations from the limit theories. The application of strategies to enable multiband (resonant), continuous multiband (frequency independent), and instantaneous, ultra-wideband antennas are discussed qualitatively. Advantages, disadvantages, and design trade-off strategies for different types of antennas are compared from a system-level perspective. A design example for a compact ultra-wideband (UWB) antenna is presented for a software-defined platform. The example involves a direct-conversion radio developed in Wireless@VT that uses a Motorola RFIC having a 100 MHz?C6 GHz operational frequency range with a 9 kHz?C20 MHz channel bandwidth. The example antenna covers frequencies from 450 MHz to 6 GHz instantaneously with approximately 5-dBi realized gain over a finite-size ground plane, including return loss and omni-directional coverage. 相似文献