空气隙对矩形微带天线性能的影响

The Effect of the Air Gap on the Performance of Rectangular Microstrip Antennas

论述了通过引入空气隙来改变矩形微带天线性能。首先,根据修改的微带天线的腔模理论,利用电磁场理论推导了具有空气隙的矩形微带天线的等效介电常数和谐振频率的理论计算公式。然后,考虑了边缘场的影响,引入了有效介电常数,对谐振频率的理论公式进行了修正。同时,应用等效原理和镜像原理推导出辐射方向图。最后,对于空气隙高度为不同数值的情况给出矩形微带天线的谐振频率和辐射方向图的数值结果,与文献[1]实测结果很吻合。

Improving the performance of rectangular microstrip antennas by importing air gaps is discussed. Firstly, an equivalent dielectric constant of rectangular microstrip antennas with air gaps and an accurate expression of resonant frequency are deduced by using electromagnetic field theory according to the modified theory of cavity model.Secondly, some influences of fringing field are taken into account , an effective dielectric constant is introduced ,and the resonant frequency expression is modified as well. At the same time, radition patterns are deduced by using equivalence principle and image theory. Finally, the calculated results for the resonant frequency and radition patterns are presented for different values of the air gap height ,which agree with the experimental results from .