探地雷达天线近地效应研究

Research on the Near Surface Effect of the Radar Antenna

微带天线应用于探地雷达技术领域时 ,实验测得的各种电参数与自由空间相应的电参数总有一定的偏差 ,这种偏差称之为近地效应。文中对天线贴地后有效介电常数的计算公式进行了修正 ,并应用该修正式对探地雷达天线回波频率进行了模拟计算 ,将计算结果与实验结果进行了对比 ,研究表明 ,有效介电常数的变化是产生近地效应的一个重要原因。

All kinds of parameters show some difference from that of freedom-space as the microstrip antennas are near the earth. The difference is called near surface effect in this paper. The formulas of effective medium dielectric constant have been modified in this paper. The simulation calculation which uses the modified formulas of effective medium dielectric constant due to the frequency of echo waves which are produced by radar antennas near the earth and compared the experiment results with the simulation calculation results. Research shows that the change of effective medium dielectric constant is the important cause which brings about the near surface effect of the antenna.