小型化平面螺旋天线及其宽频带巴伦的设计.pdfVIP

14 6 ( ) V o.l 14 N o. 6 2008 12 JOU RNAL OF SHANGHA I UN IVER SITY ( NATURA L SC IEN CE) D ec. 200 8 200 8) 1 1 1, 2 1 朱玉晓, 钟顺时, 许赛卿 , 张丽娜 ( 1. , 200072; 2. , 31400 3) , , 0. 95 ~ 15. 20 GH z , - 10 dB, 1. 4 ~ 10. 2 GH z ( 4 dB) . , , , 3 dB ( 130) . , , . ; ; ; TN 82 A Design ofM iniaturized Planar SpiralAntenna and ItsW ideband Balun ZHU Y ux iao, ZHONG Shunshi, XU Saiqing, ZHANG L ina ( 1. Schoo l o f Comm un ication and Inform ation Eng ineer ing, Sh angh ai U niversity, Sh angha i 200072, China; 2. Zhejiang Zhengyu an E lectr ic Co. , L td. , J iax ing 3 14003, Zhej iang, Ch ina) Abstract: Th is p aper introdu ces a m in iaturized planar sp iral an tenna w ith a very w ide bandw idth. In the frequ ency range from 0. 95 GH z to 15. 20 GH z, the m easured return loss is less than - 10 dB. Good c ircular po larizat ion perform ance ( ax ial rat io 4 dB ) is ob tained betw een 1. 4 GH z and 10. 2 GH z. Com pared w ith the conventional sp iral antenna, the proposed antenna sign if icantly redu ces the size and effic ien tly broaden s the 3 dB beam w idth to abou t 130 by adding a conical b ack cav ity beneath the antenna. M oreover, a w ideb and b alun is designed using an exponentia lly tapered m icrostrip para llelline w ire. S mi ulat ion and exp ermi ental resu lts show th at the proposed antenna is o f good circu lar polarization and w ideb and ch aracteristics. Key words: planar sp iral antenna; m in iaturization; w ideband ba lun; b ac