中文摘要：

提出了在普通倒F天线的两侧和底部同时添加寄生单元的改进倒F天线,该天线与普通的倒F天线相比有更宽的带宽。设计了一个工作于中心频率1.2GHz的改进倒F天线。对该天线的电气特性进行了仿真计算,并对天线主要结构参数对谐振频点和阻抗带宽的影响进行了详细分析。该天线相对带宽达到了33%（VSWR〈2）,约为普通倒F天线阻抗带宽的4倍,有效地展宽了传统倒F天线的工作带宽,在宽带通信系统中有较好的应用前景。

英文摘要：

In this paper, an improved low-profile inverted-F antenna is presented. Compared with conventional inverted-F antenna, this antenna can produce wider frequency bandwidth by adding parasitic elements on two sides and in the bettom simultaneously. The influence of primary structure parameters on the input impendence and resonance frequency is analyzed. Based on the study above, an improved low-profile inverted-F antenna with three parasitic elements at 1.2GHz is designed, simulated and analyzed. It can be concluded from the good result that the frequency bandwidth can reach 33% for a VSWR = 2, which is more than four times as wide as that of a conventional inverted-F antenna. This antenna has great potential in practical application.