基于交替投影法的多波束反射阵天线设计

Design of Multi-Beam Reflect-Array Antenna Using Alternating Projection Method

针对传统方法设计的多波束反射阵天线增益低、存在波束偏移等问题,通过将阵列综合理论中的交替投影法引入到多波束反射阵天线设计中,对相位分布进行精确求解,以提高天线性能。为验证其有效性,设计并制作了一副Ku频段、电尺寸为7.5λ0×7.5λ0的单馈源四波束反射阵天线。中心频率(12GHz)实测增益为19.1dB,效率为45.8%,带宽达到10.83%(11.2GHz^12.5 GHz),仿真和实测结果较吻合。相比于传统方法设计的多波束反射阵天线增益提高2dB以上,副瓣电平降低4.5dB以上。结果表明交替投影法求解的相位分布更加准确,能有效提高多波束反射阵天线性能。

Problems with gain, beam squint, etc conventional design of multi-beam reflect-array antennas are low antenna which are addressed in this paper by introducing the alternating projection method in array synthesis theory into the design of multi-beam reflect-array antennas in order to calculate the phase distribution precisely and improve the antenna performance. A Ku-band single-feed quad-beam reflect-array antenna is designed and manufactured with an electric size of 7.5λ0 ×7.5 λ0. Test gain at center frequency is 19. ldB with an efficiency of 45. 8% , bandwidth reaches 10.83% （ll.2GHz- 12.5 GHz）. Simulation results and measurement results match well. Com- pared to conventional designing methods, the antenna gain improves more than 2dB, and SLL de- creases more than 4.5dB. The results show that alternating projection method can not only calculate the phase distribution more precisely and but also improve multi-beam reflect-array antenna perform- ance greatly.