一种基于超材料的小型化宽带微带天线

分别将创新设计的“四方形”超材料单元和周期条形缝隙蚀刻在普通微带天线的辐射贴片和接地板上,设计了工作在3.67~14.17 GHz 的一种小型化宽带高增益微带天线。与原始的天线相比,新型天线的谐振中心频率降低了44.8%,相对带宽从2.7%扩展到243.1%,同时保持了良好的增益。实物测试结果与仿真结果吻合较好。因为超材料的左手传输特性影响了微带天线介质基板的等效媒质参数,导致天线的辐射场主要集中在水平方向,而不是传统的微带天线的垂直方向。     

C波段超材料基板高增益微带天线

针对普通微带天线增益较低的缺点,在普通微带天线上引入带有双面树枝状结构的新型负磁导率材料作为天线的基板,设计了中心工作频率为5.28 GHz的微带天线,对此天线的性能进行了研究.结果表明,通过引入负磁导率材料,天线的性能有了显著的改善,侧向辐射减弱,前向辐射增强,相对于普通微带天线,负磁导率材料微带天线的增益最大提高了2.47 dB,E面方向图的半功率波束宽度收缩了21.93°.     

基于皱褶软地表面的微带天线的研究

研究了基于皱褶软地表面的微带天线。通过对普通微带天线和采用软地表面的微带天线的输入回波损耗、辐射方向图、带宽和增益等的比较，发现该结构的软表面可以增加天线的带宽，抑制天线的背瓣，并使H面的辐射方向图和E面趋于一致。     

新型小型化圆极化微带天线

本文介绍一种新颖的单馈点圆极化矩形微带天线，它利用新型磁性材料基片和开槽设计实现了小型化。文中基于时域有限差分法分析，给出了矩形贴片中心槽和边槽不同尺寸对天线输入阻抗和反射系数的影响，并得出其设计原则，同时给出了实验天线的测试结果。实验天线的圆极化轴比带宽（小于3dB)约为3.5%，而阻抗带宽（驻波比小于2）达12.6%，约为常规设计的5.5倍，而其尺寸比常规矩形微带天线减小了40％以上。可见这种设计可以满足一些实际应用（如GPS天线）的需要。     

一种双层宽频微带天线的设计

提出一种紧凑型双层微带天线,在贴片上开"十"形缝隙来实现天线的双频带,通过加载短路探针和接地板挖槽的方法降低天线的谐振频率,提高带宽和实现小型化。利用电磁仿真软件HFSS 13.0对天线进行了仿真,仿真结果表明,该天线在回波损耗小于-10.0 d B时,天线工作频段为2.38~2.77 GHz,带宽约为390 MHz,天线的相对带宽为15.15%,天线的尺寸相对于普通微带天线降低了65.41%,该天线的带宽有很大的提高,且结构简单易实现,可用于无线通信系统中。     

W波段小型化低交叉极化片上天线

针对W波段毫米波片上雷达系统的小型化、高集成度、低功耗应用,本文基于0.13μm Bi-CMOS工艺提出了一种工作在94 GHz的小型化新型短路微带片上天线。该天线基于传统四分之一波长短路微带天线(Shorted Patch Antenna, SPA)结构,通过引入对称反向接地的寄生SPA,显著降低了天线H面的交叉极化。同时寄生SPA引入了新的谐振点,有效提高了天线的带宽。为了实现小型化的应用,本文通过引入容性加载,进一步减小了片上天线的尺寸。天线馈电采用共面集成波导(CPW)直接馈电形式,以便于毫米波GSG探针平台的测试。仿真结果显示,天线增益约为-3.2 dBi,-10 dB相对带宽为4.4%,E面、H面交叉极化分别为53.7 dB和28 dB,辐射效率大于10%。与传统四分之一波长短路微带天线相比,提出的天线-10 dB相对带宽提高了2.5%,H面交叉极化降低了16.5 dB,天线尺寸缩小了32.5%。     

一种K波段电磁超材料的设计及其在微带天线中的应用

根据电磁材料的相关理论,设计出一种由新型谐振器和金属线组成的电磁双负超材料,即介电常数和磁导率同时为负的电磁材料。新型谐振器通过较小谐振腔并联的方式,在较大的单元尺寸下提高了谐振频率,既使该电磁超材料在K波段实现了双负特性,又保证了材料的辐射面积,克服了高频段超材料由于尺寸太小而难以应用的困难。设计出一种K波段的微带天线,将新型谐振器加载在天线上,并用HFSS软件对未加载谐振器和加载谐振器的天线进行仿真对比。仿真结果表明,相比普通天线,加载新型谐振器的微带天线性能得到明显提升,驻波比2 d B以下的带宽增加了58.3%,增益变大,并且由于谐振器对天线副瓣的抑制,提高了天线的方向性。     

基于人工电磁材料的微带贴片天线频带展宽

提出一种以人工电磁材料作为介质基板的矩形微带贴片天线。通过改变人工电磁材料各单元的几何尺寸来控制介质基板的参数变化,以构成非均匀介质基板,使得贴片辐射边的辐射性能提高,从而有效提高了带宽。对设计的非均匀介质微带天线使用HFSS软件仿真。结果表明,普通均匀介质微带天线电压驻波比VSWR≤2时带宽只有0.5GHz,相对带宽为6.7%,而以人工电磁材料为非均匀介质基板的微带天线VSWR≤2时带宽达到1.6GHz,相对带宽达到20.0%。     

一种超宽带平面准八木微带天线的设计

准八木微带天线是一种结构变形的平面八木微带天线,具有较好的性能,但其带宽性能还不能满足实际应用需要。为了实现天线的超宽带性能,采用能有效地展宽天线带宽性能的蝶形振子作为激励振子等设计方法,研究出了一种新型天线。使用电磁仿真软件Ansoft HFSS对该天线进行了优化设计、仿真实验,并制作了实物天线,进行了测试。实测结果表明,该天线在中心频率2.4 GHz处具有39.6%的相对带宽(VSWR<2)和较好的方向图性能。     

一种新型小型化微带天线的分析与设计

针对传统微带天线低频端尺寸较大的缺点,设计了一种新型微带天线结构,即通过采用在传统微带天线贴片下方挖出凹槽,将辐射板放入凹槽中的办法,设计了一副小型化微带天线。与普通微带天线相比,新型天线谐振频率降低了870MHz,阻抗带宽从原来的170MHz增至560MHz,且天线在整个工作频段内具有良好辐射特性,从而验证了该设计方案的正确性。     

Broadband quasi-microstrip antenna

A new printed microwave antenna is presented. The antenna is a hybrid between a wire antenna array and a microstrip patch antenna. Although the size, cost, and efficiency are comparable to the microstrip patch, the voltage standing wave ratio 2:1 bandwidth of the antenna presented here is above 20%. The radiation pattern of the antenna does not change appreciably within the bandwidth, and the theoretical efficiency for optimal antennas remains above approximately 80% within the bandwidth. Measurements on several antennas around 2 and 4 GHz are presented, as well as theoretical results obtained using a full-wave analysis     

Investigation of a Compensated Rectangular Microstrip Antenna With Negative Capacitor and Negative Inductor for Bandwidth Enhancement

New broadband impedance matching circuits used to increase the impedance bandwidth of the microstrip antennas for transmit applications are proposed and analyzed. A microstrip patch operating at 10.5 GHz having 12.2% bandwidth has been utilized as a reference antenna. The impedance bandwidth of the antenna has been enhanced by using negative capacitance and inductance compensation networks from 12.22% to 16.96% and 24.50%, respectively. In addition, it has been shown that the active compensation significantly improves the radiation pattern     

Broad-band gap coupled microstrip antenna

A microstrip antenna with large bandwidth is developed using a parasitic technique. Compared to the available wideband antennas, the proposed antenna structure is very compact and gives a less distorted radiation pattern with frequency. An impedance bandwidth eight times that of a conventional patch antenna of the same size is achieved. The concept of coupled microstrip line model is extended for theoretical interpretation of the impedance loci. The experimental procedure and results are described, and a theoretical analysis is presented     

Hybrid-coupled broadband triangular microstrip antennas

Two broadband configurations consisting of three hybrid-coupled equilateral and isosceles triangular microstrip antennas have been proposed. Both configurations yield more than four times the bandwidth as compared with the corresponding single triangular microstrip antenna. The radiation pattern of a hybrid-coupled isosceles triangular microstrip antenna is in the broadside direction with very small variation over the entire bandwidth. In addition, this antenna has wide half power beamwidth, making it suitable as an element for the large scan broadband antenna array.     

宽带毫米波微带天线的设计与分析

根据微带天线的设计技术要求,介绍了微带天线带宽的影响因素。在矩形毫米波微带天线设计与分析的基础上,分别设计出 C 型和 W 型两种宽带毫米波开槽微带天线。利用仿真软件对3 种天线的输入回波损耗、驻波系数、相对带宽和方向性等技术参数进行仿真优化和比较分析。仿真与实验结果表明,3 种天线的设计均满足技术要求,C 型和 W 型开槽微带天线较矩形微带天线的相对带宽大幅提高,且具备良好的定向辐射特性。     

Thin-film HTS planar antennas

The “H” microstrip antenna is suitable for use as an efficient small antenna when it is constructed out of superconducting thin-film materials. An aperture feed and matching network is described which provides a convenient enhancement of the capabilities of the “H” antenna. Methods of prediction of the center frequency are given. In addition, an analytical expression is developed for the far field radiation pattern of the “H” antenna and the efficiency and Q of superconducting and copper antennas are described using this expression. It is likely that superconducting antennas will only have significant application when they are used in arrays. Three arrays are described demonstrating multiband self-diplexing multifrequency-enhanced bandwidth and multifrequency beam forming     

超宽带阶梯形微带单极子天线的设计与研究

针对当前已有超宽带(ultra-wideband,UWB)微带单板子天线带宽窄、尺寸大等缺陷,设计了一款小型化UWB阶梯形微带单极子天线,采用开槽的矩形辐射贴片、阶梯形微带馈电线和缺陷地面结构(defected ground structure,DGS)实现良好的UWB特性.对天线的回波损耗、电压驻波比(voltage...     

Enhanced patch-antenna performance by suppressing surface wavesusing photonic-bandgap substrates

The microstrip patch antenna is a low-profile robust planar structure. A wide range of radiation patterns can be achieved with this type of antenna and, due to the ease of manufacture, is inexpensive compared with other types of antennas. However, patch-antenna designs have some limitations such as restricted bandwidth of operation, low gain, and a potential decrease in radiation efficiency due to surface-wave losses. In this paper, a photonic-bandgap (PBG) substrate for patch antennas is proposed, which minimizes the surface-wave effects. In order to verify the performance of this kind of substrate, a configuration with a thick substrate is analyzed. The PBG patch antenna shows significantly reduced levels of surface modes compared to conventional patch antennas, thus improving the gain and far-field radiation pattern     

一种新型2.4GHz频段加载贴片天线的设计

采用在贴片上开槽和加载的方法,设计了一种用于2.4GHz频段无线通信设备、内缩渐变线馈电的新型结构贴片天线.给出仿真设计的性能和多个天线样品的实测输入驻波比曲线和远区辐射特性图,详细研究分析了不同加载条件、不同辐射边尺寸对输入驻波比的影响.实测结果表明,该天线在2.4GHz频段上获得超过15%的相对带宽(VSWR<2),而且尺寸比相应频段的微带贴片天线更加微型化.     

Ultra-wideband antipodal slot antenna with improved radiation performance

A novel antipodal wide-slot antenna for ultra-wideband (UWB) applications is proposed and studied in detail. The antenna is fed by a microstrip line terminated with a rectangular tuning patch. An antipodal structure is employed to improve the radiation performances. The return losses, surface E-field, current distribution, radiation patterns and gains of the antenna are numerically and experimentally investigated. Results show that the proposed antipodal antenna has an impedance bandwidth from 0.79 to 4.0?GHz, which is about 5:1. Compared with conventional rectangular wide-slot antenna, more stable radiation pattern with lower cross-polarisation level and flatter gain variation over a 3:1 bandwidth can be obtained. Thus, the proposed antenna should be more suitable for future UWB-multiple-input multiple-output applications using polarisation diversity than conventional UWB rectangular slot antennas.