亚洲免费av电影一区二区三区,日韩爱爱视频,51精品视频一区二区三区,91视频爱爱,日韩欧美在线播放视频,中文字幕少妇AV,亚洲电影中文字幕,久久久久亚洲av成人网址,久久综合视频网站,国产在线不卡免费播放

        ?

        A method of elimination of undesired resonant points of microstrip antenna by cutting U-shaped slot on the ground

        2014-09-07 06:37:52TENGFeiCHENGXiuyang

        TENG Fei,CHENG Xiu-yang

        (College of Electrical Engineering and Automation,Shandong University of Science and Technology,Qingdao 266590,China)

        0 Introduction

        With development of the microstrip antenna,circular polarization microstrip antenna has been wildly used because of the advantages of low profile[1],conformal,easy integration and low cost,etc..

        In the Ref.[2],the author uses square patch and realizes circular polarization characteristics with cross slot,and axial ratio bandwidth of the circular polarization is 1.4%. In the Ref.[3],while perturbation method is used,the patch with corner cut realizes the circular polarization characteristics,and axial ratio bandwidth of the circular polarization is 1%. Here we design a dual-layer circular polarization microstrip antenna by cutting a rectangular aperture on the patch,but the antenna has some resonant points undesired. So we should eliminate these undesired resonant points by slotting on the ground[4,5].

        1 Structure of designed antenna

        The structure of designed antenna is shown in Fig.1. It's microstrip antenna of two layers medium. The purpose of cutting a rectangular aperture of 45°is to form a circular polarized wave. And sizes of the antenna are as follows:l1=89.23 mm,w1=89.23 mm,l2=20.87 mm,l3=14.6 mm,w2=4.84 mm,l4=19.8 mm,w3=1.8 mm,θ=45°,h1=1.6 mm,h2=1.87 mm.

        Fig.1 Structure of designed antenna

        Based on the design,we use the electromagnetic simulation software to build up the antenna model and simulate. The simulation results are shown in Fig.2.

        From Fig.2,we know that the frequency of the resonant point is 2.42 GHz. However,there are two undesired resonant points,the frequencies of which are both greater than the resonant frequency. One is around 4.4 GHz,the other is around 5.8 GHz.

        Slotting with an appropriate size on the ground can generate high impedance at the corresponding frequency point. In the way,the conduction and radiation of the corresponding frequency wave can be suppressed,and the same way applies to the corresponding frequency. Thus,we eliminate the undesired resonant points by slotting on the ground.

        Fig.2 S11 of the antenna

        2 Elimination of resonant frequency point of 5.8 GHz

        In order to eliminate the resonant frequency point of 5.8 GHz,we open aU1-shaped slot on the ground of the antenna. Shape of the slot is shown in Figs.3-4.

        Fig.3 Diagram of U1-shaped slot on the ground

        Fig.4 Diagram of slot on the ground of antenna

        From the above analysis we know that the length of theU1-shaped slot is half of the wavelength of corresponding frequency point of 5.8 GHz,soL=L1+L2+L3=25 mm.

        Based on the above design we use the electromagnetic simulation software to build up the antenna model and simulate. The simulation results are shown in Fig.5.

        Fig.5 S11 inhibition of 5.8 GHz

        From Fig.5 we know that the resonant point of 5.8 GHz can be inhibited greatest whenL=25 mm. The result of simulation is illustrated above. As shown in the Fig.5,the resonant depth at 5.8 GHz can be inhibited to -5 dB. So we eliminate the resonant frequency point of 5.8 GHz by cutting aU1-shaped slot on the ground.

        3 Elimination of resonant frequency point of 4.4 GHz

        Similarly,in order to eliminate the resonant frequency point of 4.4 GHz,we open aU2-shaped slot shown in Fig.6 on the ground of the antenna.

        Fig.6 Diagram of U2-shaped slot on the ground

        In the same way,length of theU2-shaped slot is half of the wavelength of corresponding frequency point of 4.4 GHz,soL′=L4+L5+L6=37 mm,and the simulation results are shown in Fig.7.

        From the results we know that the resonant depth at 4.4 GHz can be inhibited to -7 dB. So theU2-shaped slot opened on the ground can eliminate resonant frequency point of 4.4 GHz effectively.

        Fig.7 S11 inhibition of 4.4 GHz

        4 Conclusion

        In this paper,we propose a method to eliminate undesired resonant points of designed microstrip antenna by cuttingU- shaped slots on the ground. In the wayS11of 4.4 GHz and 5.8 GHz are both greater than -10 dB,so the undesired resonant frequency points of 4.4 GHz and 5.8 GHz can be eliminated effectively.

        [1] ZHONG Shun-shi. Microstrip antenna theory and application. Xi 'an: Xi'an University of Electronic Science and Technology Press,1991.

        [2] CHEN Wen-shyang,WU Chun-kun,WONG Kin-lu. Novel compact circularly polarized square microstrip antenna. IEEE Transactions on Antennas Propagation,2001,49(3): 340-341.

        [3] WONG Kin-lu,WU Jian-yi. Sing-feed small circularly polarized square microstrip antenna. Electronics Letters,1997,33(22): 1833-1834.

        [4] Zolfagharian A R,Azarmanesh M N,Qjaroudi M. Ultra wide band small square monopole antenna with variable frequency notch ban characteristics. Microwave and Optical Technology Letters,2012,54(1): 262-267.

        [5] WONG Kin-lu,LIN Yi-fang. Circularly polarized microstrip antenna with atuning stub. Electronics Letters,1998,34(9): 831-832.

        亚洲一区二区三区一站| 内射无码专区久久亚洲| 国产av一区二区三区在线播放| 国产精品国产三级国产av品爱网 | 久久久久国产综合av天堂| 亚洲国产美女精品久久久久| 音影先锋色天堂av电影妓女久久 | 999久久久免费精品国产牛牛| 五月婷婷丁香视频在线观看| 少妇久久久久久被弄高潮| 国内精品久久久久久中文字幕 | 免费观看在线视频一区| 国产嫩草av一区二区三区| 国产又a又黄又潮娇喘视频| 免费成人毛片| 日本精品一区二区三区在线播放 | 特黄a级毛片免费视频| 女同性恋精品一区二区三区| 国产精品国产三级农村妇女| 色爱情人网站| 亚洲精品无播放器在线播放| 亚洲国产精品久久九色| 亚洲97成人精品久久久| 国产精品videossex久久发布| 中文字幕乱码人妻一区二区三区| 456亚洲人成在线播放网站| 视频一区视频二区自拍偷拍| 一区二区三区视频| 国产亚洲婷婷香蕉久久精品| 大肥婆老熟女一区二区精品| 中文字幕有码人妻在线| 亚洲国产成人精品无码一区二区| 国产免费一级在线观看| 一级二级三一片内射视频| 国产极品粉嫩福利姬萌白酱| 亚洲一区精品无码色成人| 不卡a v无码在线| 国产精品亚洲一二三区| 国产伦精品免编号公布| 亚洲激情成人| 国产麻豆成人精品av|