通过参照金属环天线的构造,自行研制了方环等离子体天线,并借鉴金属天线的测量方法,建立等离子体天线测试系统,对该天线的阻抗特性、辐射特性进行了实验研究。发现,输入电阻在160～350MHz都靠近50Ω,电抗接近0,驻波比低于2,具有非常宽的带宽。而且在频率较低的情况下该天线的增益和与之构造相同的方环金属天线接近。在200MHz试验频率下方环等离子体天线具有较高的方向性。 By referring to the structure of metal loop antenna, a square-loop plasma antenna was developed by ourselves and the measurement method of metal antenna was used to establish a plasma antenna test system. The impedance and radiation characteristics of the antenna were experimentally studied. It is found that the input resistance is close to 50Ω at 160 ~ 350MHz, the reactance is close to 0, the VSWR is lower than 2, and has a very wide bandwidth. And in the case of lower frequencies, the gain of the antenna is close to that of a square-loop metal antenna of the same configuration. The toroidal plasma antenna has a high directivity at a frequency of 200 MHz.