多频共面波导馈电平面开式套简天线研究

提出了一种同时支持诸多频带工作的共面波导馈电平面开式套筒天线.共面波导中心金属导带以及接地板均采用渐变的形状,天线采用开式套筒结构,并加入了一个倒L型寄生贴片,以最大程度地展宽天线带宽.与以往所提出的共面波导馈电天线相比,此天线具有尺寸小,覆盖更宽的频带,可同时支持个人通信系统(PCS),宽带码分多址系统(WCDMA)...     

一种用于WLAN/WiMAX的小型三频带印刷单极天线

设计了一种满足WLAN和WiMAX工作所需的小型共面波导馈电的三频带印刷单极子天线单元。该单极子天线的设计采用了在倒锥形单极天线表面开缝和在底层加载枝节的结构,使其获得了小型化和三频带的性能。采用基于共面波导的馈电方式,使天线单元具备宽带匹配、结构简单、制作方便和易与其它无线通信设备集成等优点。仿真和实测结果表明,设计的天线单元在WLAN和WiAMX应用的频段上10dB阻抗带宽分别约为610MHz(2.10～2.71GHz,约25.4%),310MHz(3.48～3.79GHz,约8.9%)和360MHz(4.96～5.32GHz,约7%),增益也都在2dB以上,而且在相应工作频点上辐射方向图全向性较好。该天线能满足WLAN和WiMAX的应用所需,具有较高的工程应用价值。     

一种地面开槽的双频宽频单极子天线

针对无线通信应用,设计了一种双频单极子天线,天线由共面波导馈电。天线的整体尺寸为30 mm×25 mm×0.8 mm,基板选用FR4。天线在平面单极子的基础上,通过在共面波导地平面上开槽,实现了双频特性;同时采用具有渐变结构的单极子贴片,实现了在较宽频带上良好的阻抗匹配。采用HFSS仿真软件对天线进行仿真,仿真结果表明:天线具有单极子天线的辐射特性,天线带宽较宽,在3.01~6.1 GHz反射损耗小于-10 d B,相对带宽达到了67.8%,工作频段覆盖了3.5/5.2/5.5/5.8 GHz频段。天线具有较好的全向辐射方向图和增益,其尺寸小、结构简单和易于加工,能够广泛用于WLAN和WiMAX通信系统中。     

一种用于WLAN的小型双频宽带印刷单极天线

设计了一种满足WLAN双频工作所需的小型共面波导馈电的双频宽带印刷单极子天线单元.该单极子天线的设计采用了在倒锥形单极天线顶部添加半圈矩形螺旋枝节的结构,使其获得了小型化和双频宽带的性能.采用基于共面波导的馈电方式,天线单元具备宽带匹配、结构简单、制作方便和易与其它无线通信设备集成等优点.仿真和实测结果表明,设计的天线单元在WLAN应用的高、低频段上10dB阻抗带宽分别约为2100MHz(4.52～6.62GHz,约37.7%)和220MHz(2.27～2.49GHz,约9.2%),增益在2～3dBi之间;在相应工作点辐射波瓣图上全向性较好.该天线能满足WLAN应用所需,具有较高的工程应用价值.     

改进共面波导馈电的双频单极子天线设计

介绍一种具有全向性的印刷单极子天线。该天线由简单的平面单极子和共面波导（CPW）组成。通过改变共面波导的特性阻抗,可以使共面波导成为第二个独立辐射设备从而使得该单频结构天线产生双频性能。仿真及其实验结果表明,该结构可以获得很大自由度的双频性能（包括WLAN等）。还可以将两个频段融合实现宽带性能,并获得大于66%的相对带宽（VSWR〈2）。     

一种共面波导馈电的圆极化天线的设计

RFID系统在当今社会应用广泛,天线在RFID系统中的作用尤其重要,圆极化天线的设计大大提高了系统的灵活性和可靠性。给出了一款通用频带的特高频RFID 阅读器天线。该天线通过共面波导馈电,在介质层顶部的接地平面刻蚀方形槽,为了增加天线阻抗带宽,将共面波导馈线弯折设计;为了提升天线的圆极化性能,在槽内适当添加L 型连接线。该天线实现了410 MHz的阻抗带宽和488 MHz的轴比带宽,天线尺寸为115 mm*115 mm*0.3 mm。     

车载电话用双频共面振子天线的设计

设计了一个用于车载电话的双频共面振子天线.为获得在同轴馈电时天线振子的平衡馈电,该设计使用了共面波导馈电结构.仿真计算结果给出了天线振子双臂的电流分布,并显示设计的共面振子天线在两个不同的频率上工作.实际设计天线的测试结果表明,在两个频带824MHz～896MHz和1850MHz～1990MHz内,设计天线的驻波比都小于2,而在水平面内的平均增益都大于指标值.     

用于ISM/UNNI频段的新型双频单极子天线设计

针对天线在ISM和UNNI频段的应用,提出了一种采用共面波导馈电的新型单板子双频天线,在传统T型单极子天线上平行加载辐射贴片实现双频工作.分析了天线尺寸变化对工作频率的影响,得出所设计的天线频率比在1.67～2.67范围內可调.制作加工了工作于ISM/UNNI频段的天线实物,测试结果与实验结果吻合良好.天线全向辐射性能...     

应用于WiFi/WiMAX的三频超介质加载天线

以研究超介质结构在天线中的应用为目的,采用了超介质理论中的负折射率传输线(NRI-TL)加载技术,设计了一种三工作频段的单极子贴片天线.该单极子天线由不均匀弯折线构成,采用共面波导(CPW)馈电.在2.45 GHz和55 GHz附近弯折线与超介质结构可形成折合单极子辐射;在3.55 GHz附近超介质结构可改变天线表面电...     

FR4基板金属底板共面波导传输线阻抗特性研究

为了提高基于FR4基板的射频电路板天线端口阻抗匹配的性能,利用FDTD方法对基于FR4基板的金属底板共面波导传输线特性阻抗与端口回波损耗进行了计算.在理论分析的基础上,对FR4基板金属底板共面波导传输线进行了实际的加工,加工的基板厚度为1.5mm,中心导带分别为1mm、1.5mm和1.7mm,槽宽分别为0.2mm、0.3mm和0.4mm.利用矢量网络分析仪在1MHz～3GHz频段内对S11进行了测试,从测试结果可以看出,高频部分与理论计算结果比较一致,3种尺寸的金属底板共面波导传输线回波损耗均在-10dB以下,考虑加工误差与焊接工艺,第3种结构的阻抗匹配性能最好.     

Compact CPW-fed dual-frequency monopole antenna

By introducing an extended conductor line to a rectangular meander monopole, a novel compact dual-frequency monopole antenna is proposed. The proposed antenna is fed using a 50 /spl Omega/ CPW transmission line, is printed in a single metal layer, and therefore is easily constructed. The designed antenna can operate at 900 and 1800 MHz bands and provide sufficient bandwidths for the GSM and DCS systems, respectively.     

Triple-band CPW-fed compact monopole antennas for GSM/PCS/DCS/WCDMA applications

A triple-band coplanar waveguide (CPW)-fed LI-shaped monopole antenna is proposed. The antenna is composed of an I-shaped monopole and a meandered L-shaped one. The dimensions of the design are 29 times 28 mm which are 0.077 lambda times 0.075 lambda in terms of the lowest operating frequency of 800 MHz. The antenna operation presents attractive characteristics, each monopole is independently optimised to the resonant frequency and the impedance bandwidth without affecting those of other bands. The antenna shows improved radiation efficiency of individual monopoles for a global system for mobile communication, personal communication systems, digital communication systems, and wireless code division multiple access applications.     

一种应用于WLAN 的双频对称型单极子天线

设计了一种应用于无线局域网的由共面波导馈电的双频单极子天线。该天线在2.45 和5.5 GHz 频率下谐振,其(10 dB)阻抗带宽分别为2.40～2.52 GHz 和4.80～7.30 GHz,覆盖了无线局域网2.4/5.2/5.8 GHz 的工作频带。另外,在工作频带内,还获得了良好的全向辐射方向图和天线增益。     

Multiband Printed Monopole Slot Antenna for WWAN Operation in the Laptop Computer

A multiband printed monopole slot antenna promising for operating as an internal antenna in the thin-profile laptop computer for wireless wide area network (WWAN) operation is presented. The proposed antenna is formed by three monopole slots operated at their quarter-wavelength modes and arranged in a compact planar configuration. A step-shaped microstrip feedline is applied to excite the three monopole slots at their respective optimal feeding position, and two wide operating bands at about 900 and 1900 MHz are obtained for the antenna to cover all the five operating bands of GSM850/900/1800/1900/UMTS for WWAN operation. The antenna is easily printed on a small-size FR4 substrate and shows a length of 60 mm only and a height of 12 mm when mounted at the top edge of the system ground plane or supporting metal frame of the laptop display. Details of the proposed antenna are presented and studied.      

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.     

A compact four‐element MIMO antenna for WLAN/WiMAX/satellite applications

This paper presents a four‐element wideband monopole MIMO antenna. Initially, a single‐element wideband CPW‐fed antenna is designed operating in the range of 4.30 to 6.45 GHz. Using this design, an approach towards MIMO structure is studied. A two‐element structure is designed keeping them adjacent to each other, and the isolation between the antennas is observed. After which, a four‐element structure is designed having the best orientation in order to achieve good isolation between the antenna elements. The proposed antenna configuration has four identical CPW‐fed elements. The proposed configuration has a fractional bandwidth of 40.27% and has a simulated peak gain of 5.5 dBi. This antenna is intended to be used for WLAN, WiMAX, and satellite bands of range corresponding to 4.70–6.19, 5.5–5.7, and 5–6 GHz. All the necessary antenna simulations are simulated using Ansys HFSS and verified on NI AWR Design Environment. The fabricated model of the proposed design is measured for its performance parameters and validated.     

A CPW-fed dual-frequency monopole antenna

A new dual-frequency design of coplanar waveguide (CPW)-fed monopole antenna is proposed and experimentally studied. The proposed antenna utilizes the advantages of the CPW line to simplify the structure of the antenna into a single metallic level, thereby making easier the integration with the microwave integrated circuits. The two operating modes of the proposed antenna are associated with various lengths of two monopoles, in which the longer monopole works for the first resonant mode and the shorter monopole works for the second mode. Moreover, by increasing the width of the longer monopole, a broadband dual-frequency operation is demonstrated. Experimental results show that the impedance bandwidth, determined from 10-dB return loss, of the two operating frequencies can both be greater than 14%. Details of the experimental results are presented and discussed.     

Elliptical planar monopole antenna with extremely wide bandwidth

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.     

Broadband Dielectric Resonator Antenna With Metal Coating

A broadband dielectric resonator (DR) antenna is proposed, which consists of a rectangular DR coated with metal on three sides and placed on a ground plane. The structure is analyzed by modelling the dielectric-air interface as perfect magnetic conductor (PMC). A coplanar waveguide (CPW) with terminating slots is used to feed the antenna. Measurement results exhibit a wide bandwidth of about 47% over which the E_thetas pattern on the horizontal plane is nearly omnidirectional. The 10-dB bandwidth of this broadband DR monopole covers 4.2-6.8 GHz. Hence, it can be used for WLAN 802.11a applications