Developmental Study of Cavity-Backed Slot Antennas Consisting of Two Conductive Plates Separated by Wires

空腔背槽天线是太阳能卫星微波能量传输天线元件。该天线元件在机械强度、散热和低轮廓结构方面优于其他类型的天线。我们提出了一种新型的空腔背槽天线，由两个导电板由细线或粗柱隔开。首先给出了一种由短端探针激发的高度为3mm的天线单元的有效设计方法，并分别推导了有限导板和无限导板两种天线单元的天线参数。两者在2.45 GHz频率下都实现了良好的阻抗匹配。计算结果表明，天线参数对阵列天线设计是有效的，激励单元与相邻单元在h平面方向上的相互耦合相当大。对九元阵列天线和二十五元阵列天线的额外计算表明，两种阵列几何形状的回波损耗和相互耦合量几乎相同。因此，对九元阵列天线的互耦性进行评估，为大规模阵列天线的互耦性研究提供了良好的前景。其次，我们讨论了另一种由倒f元激发的天线单元。元件由两个导电板组成，中间由8根12毫米高的方柱隔开。如果我们使用金属管作为支柱，我们可以实现一个简单的方法来配置元件，因为两个导电板是用螺丝固定的。此外，所述天线配置具有这样的优点：馈线设置在所述底部导电板上，并且不与所述上板连接。这种类型的元素比前一种元素配置了更少的帖子。

The cavity-backed slot antenna is used as a microwave energy transmission antenna element for solar power satellites. The antenna element has advantags over other types of antenna in mechanical strength, heat dissipation and a low profile structure. We propose new types of cavity-backed slot antenna consisting of two conductive plates separated by thin wires or thick pillars.First we show an effective design method of an antenna element with the height of 3 mm excited by the short-ended probe and derived two kinds of antenna parameter for the element with finite and infinite conductive plates, respectively. Both realize a good impedance matching at the frequency of 2.45 GHz. It is clarified from calculations that the antenna parameters are effective for the array antenna design and that the mutual coupling between the excited element and its adjacent ones in the direction of H-plane is considerably large. Additional calculations for the nine-element and the twenty-five-element array antennas show that quantities of return loss and mutual couplings are almost the same for both array geometries. So the evaluation of mutual coupling for the nine-element array antenna gives us good perspectives of that in the large-scale array antenna.Second, we discussed another type of antenna element excited by an inverted-F element. The elements are composed of the two conductive plates separated by the eight square pillars of 12 mm high. If we use metal pipes as the pillars, we can realize an easy method to configure the element as the two conductive plates are fixed with screws. Furthermore, the antenna configuration has advantages such that the feeder is set on the bottom conductive plate and is not connected with the upper plate. This type of element is configured with fewer posts than the previous one.