采用L型馈电结构的宽带圆极化微带天线

提出一种L型微带线馈电的宽带圆极化微带天线。该天线采用威尔金森功分器级联宽带移相器作为馈电网络,产生一对超带宽正交信号。L型馈电结构利用容性耦合馈电机制,克服传统的探针馈电结构感抗过大的缺陷,实现良好的阻抗匹配。研究结果表明,天线在41.3%(2.45~3.69 GHz)的带宽内回波损耗大于10 dB;在2.46~3.69 GHz频段内顶点轴比小于3 dB,圆极化相对带宽达到41%;在中心频率3.0 GHz处天线增益为7.94 dBi。此外,天线在整个工作波段内具有稳定的天线增益和良好的辐射方向图。

A broadband circularly polarized(CP) microstrip antenna fed by L-shaped microstrip line is proposed.The antenna uses Wilkinson power divider cascaded wideband phase shifter as the feed network,resulting in a pair of over-bandwidth orthogonal signals.The L-shaped feed structure uses the capacitive coupling feeding mechanism to overcome the defect of excessive inductance of the traditional probe feed structure and achieve a good impedance matching.The research results show that the echo loss of the antenna is more than 10 dB in the bandwidth of 41.3%(2.45~3.69 GHz),the vertex axis ratio is less than 3 dB in the 2.46~3.69 GHz band,the relative bandwidth of circular polarization is 41%,and the antenna gain is 7.94 dBi at the central frequency 3.0 GHz.In addition,the antenna has stable antenna gain and good radiation pattern in the whole working band.