传统的反射阵利用相控器件与微带线实现波束赋形。为了降低相控成本与系统复杂度, 提出基于时域调制阵列波束赋形技术。时域调制反射阵列是一种基于简单可重构反射单元的反射阵, 它利用控制可重构反射单元的开与关, 达到控制阵列输出, 实现旁瓣抑制、波束赋形等功能。通过理论推导及仿真, 结果表明, 时域调制反射阵可以在不采用传统阵列中的相控器件及馈电网络的前提下, 采用最小方差无失真响应波束赋形方法与时间调制法, 生成理想的方向图, 实现波束赋形功能。此特性将有利于推广波束赋形技术在毫米波频段反射阵的应用。

Conventional reflectarrays adopt phase shifters and microstrip lines to form the beam pattern. To reduce the cost of phase control and system complexity, a beamforming technology based on time-modulated reflectarrays is introduced. The time modulated reflectarray is a kind of reflectarray antennas with simple reconfigurable reflecting elements, which can be utilized to realize many functions including sidelobe suppression and beam forming. Compared with traditional reflectarray which use microstrip lines and phase-shifting devices, the time modulated reflectarray can control the output of array by controlling the switch-on and switch-off times of reflection elements. The theoretical analysis and simulation results show that the time-domain modulated reflectarray can generate the ideal directional pattern and realize the beam forming function without adopting the phased-array units and the cooperative feeding network in the traditional phased reflectarrays. This feature will facilitate the application of beam forming technology in the millimeter-wave reflectarrays.