提出了一种基于微光学阵列差分真时延网络的光学多波束合成系统, 研究了该系统中结构参数与波束形成性能的关系。通过改进基于微光学阵列差分真时延网络的参数, 优化了差分真时延网络的初相位以及幅相一致性; 通过改进天线单元的参数结构, 优化了各个天线单元的方向图, 解决了合成波束时容易出现栅瓣及波束较宽的问题。所提系统可抑制栅瓣, 得到的旁瓣消光比大于10 dB, 频率为3.8 GHz时的3 dB带宽为35°, 频率为4.9 GHz 时3 dB带宽为29°, 指向误差小于1.5°, 频率覆盖范围为2~6 GHz。该系统在光学相控阵雷达中具有广阔的应用前景。

An optical multi-beam synthetic system based on differential true time delay network which is with micro-optical array is proposed, and the relationships among the structural parameters and the beam-forming performance of the proposed system are studied. The initial phase and the consistence of amplitude and phase are optimized when we optimize the parameters of differential true time delay network based on micro-optical array. The directional diagrams of antenna elements are optimized when we optimize the structural parameters of antenna elements, and the problems of existing grating lobe and wide beam in beamforming are solved. At last, the grating lobe is suppressed, the extinction ratio of sidelobe is larger than 10 dB, the 3 dB bandwidths are 35° at 3.8 GHz and 29° at 4.9 GHz, the steering error is less than 1.5°, and the frequency covering band is 2-6 GHz. The proposed system has wide application prospects in optically controlled phased array radar.