基于CRLH传输线的圆极化微带天线

一种基于CRLH传输线的圆极化微带天线

内容简介：提出了一种利用复合左右手传输线(CRLH TL)来设计小型圆极化贴片天线的方法。采用在天线地板刻蚀逆开口谐振环(CSRR)实现并联电感以及在贴片中央开槽实现串联电容。由于CSRR能够有效降低+1阶模式谐振频率,因此,可以缩小天线电尺寸。同时,由于 CSRR 的不对称性产生的寄生模式与+1阶模式相互正交,通过调整贴片中央的圆形宽缝可以使二者幅度相等,故而形成圆极化辐射。实验结果表明：该圆极化天线电尺寸为0.389λg×0.389λg,阻抗带宽和轴比带宽分别为16.08%和1.52%,该天线用50Ω微带线直接馈电,不需要阻抗变换线和接地过孔,易于设计加工。

Abstract：A method of designing a compact circularly polarized (CP)patch antenna is proposed based on a composite right/left-handed (CRLH)transmission line (TL)unit-cell.The CRLH TL unit-cell includes a complementary split ring resonator (CSRR)nicked at antenna floor for realizing inductance in parallel and a gap slotted at the center of a sticked plate for realizeing serial capacitance.The CSRR can decrease the TM10 mode resonance frequency,thus reducing the size of the proposed antenna.Simultaneously,the a-symmetry of the CSRR brings about a parasitical mode which crosses the +1 st-order mode orthogonally by changing the slot radius.The combination of these two orthogonal modes with 90°phase shift makes the proposed antenna form a CP property.The experimental results show that the size of the proposed an-tenna is 0.389λg×0.389λg,and the impedance bandwidth and the axial ratio bandwidth are of 16.08% and 1.52% respectively.Moreover,the proposed antenna is designed without impedance transformer,90° phase shift and ground via,and is easy to design and process.

作者：周成, 耿林, 梁建刚,

关键词：圆极化天线, 小型化, 轴比, 复合左右手传输线,