针对传统反射阵列天线不能灵活地进行波束转向,无法满足部分应用场景需求这一问题,文中设计、制作并测试了一种具有12×12个反射单元的1-bit波束可重构反射阵列。通过在两个尺寸相同的L形结构中间加载PIN二极管实现1 位可重构单元,采用Ansys HFSS 15对该单元进行建模和仿真,在4.36 GHz~5. 06 GHz频率范围内,单元在PIN二极管导通和断开两种状态下的相位差在180°±25°范围内,并在4.46 GHz 和4.96 GHz 两个频率下,具有180°相位差。对4.96 GHz进行验证,通过数字控制板独立调节每个PIN 二极管,从而实现所需的相位分布。仿真和测试结果表明反射阵可以在4.96 GHz的中心频率下实现±50°范围内的波束扫描,并且在4.76 GHz~5. 46 GHz 频率范围内,具有相对良好的波束扫描性能。此外,反射阵采用镜面对称排布方式以改善交叉极化,实测交叉极化为-26.7 dB,相比较传统排布方式,交叉极化峰值降低了15.2 dB。

In response to the problem that conventional reflectarray antennas cannot flexibly perform beam steering, which makes it unable to meet the requirements of some application scenarios, a 1-bit 12×12 beam reconfigurable reflectarray is designed, fabricated, and measured. The 1-bit reconfigurable element is realized by loading PIN diode between two L-shaped structures with the same size, the element is modeled and simulated by Ansys HFSS 15, the phase difference between the two states is within the range of 180° ± 25° over the frequency range of 4. 36 GHz~5. 06 GHz, and the phase difference of 180° occurs at 4. 46 GHz and 4. 96 GHz. To verify 4. 96 GHz, through digital control board to regulate each PIN diode independently to achieve the required phase distribution. The simulated and measured results show that the beam scanning of the reflectarray within ±50° can be achieved at 4. 96 GHz, and show a good beam scanning performance from 4. 76 GHz to 5. 46 GHz. Furthermore, the reflectarray is arranged in mirror symmetry to improve cross polarization, the measured cross-polarization level is -26. 7 dB, the peak value of cross-polarization decreases by 15. 2 dB compared with the traditional arrangement.

TN821