上天线 meaning in English

upper antenna

A patch antenna with air holes in the substrate has been designed . the finite - difference time - domain ( fdtd ) method together with the perfectly matched layer ( pml ) boundary treatment has been used to study the performance of the antenna . it is shown that the surface waves are significiently suppressed , the frequency bandwidth is improved , the sidelobe levels are reduced and consequently the gain in the forward direction is improved by 14 db ( about 4 db higher than the value reported previously )
设计了一种基底钻周期圆孔结构的电磁(光子)晶体贴片天线，用fdtd方法并结合pml吸收边界条件对该天线进行了研究，结果表明本文所设计的基底钻孔型电磁晶体贴片天线取得了多方面的性能改善，与普通天线相比，基底中的表面波受到很大抑制，天线的带宽增加，远场方向图上天线的旁瓣和背瓣被明显削弱，向前辐射的增益由原来的12db增加到26db ，增加了14db ，比文献上报道的gonzalo等人的研究结果提高了4db 。