基于SIW的频率/极化可重构背腔缝隙天线

针对现有可重构天线难以同时对频率与极化特性进行切换的不足，提出了一种低剖面紧凑型的频率与极化可重构波导背腔天线。天线由基片集成波导(substrate integrated waveguide，SIW)谐振腔和十字型槽线组成。在十字型槽线内加载PIN二极管，通过二极管的导通和断开调整有效谐振长度，达到频率可重构目的。在十字槽线两侧加载短路通孔可重构谐振腔内电场分布，在不改变辐射结构下实现圆极化波与线极化波之间任意切换。2种重构方式的切换结构各位于天线底层与顶层，二者互不影响，且天线制作简单，成本低廉。测试结果表明，天线仿真与实测保持一致，且工作性能良好。

Frequency and polarization reconfigurable cavity-backed slot antenna based SIW technology

In order to solve the deficiency that reconfigurable antennas are difficult to alter the frequency and polarization characteristics at the same time, a cavity-backed slot antenna with both frequency and polarization reconfigurable characteristic is proposed in this paper. The proposed antenna is composed of a Substrate-Integrated Waveguide (SIW) cavity and a cross-shaped slot. The frequency reconfigurable situation can be realized when four PIN diodes employed in the cross-shaped slot are on or off. Moreover, a switch between the linear polarization and right-hand or left-hand circular polarization can also be realized using only two PIN diodes and a short post, which vary the electric field distribution within the cavity but without changing the radiation antenna structure. The two switch states are separated from the bottom layer and the top layer of the antenna, which is beneficial to reduce interference, and the antenna is simple to make and low in cost. The measurement results show good agreement with simulation and excellent condition of the antenna.