一种相控阵光学天线设计方法

Design for Optical Phased-Array Antenna

相控阵天线可实现波束的电控扫描,已在微波波段获得广泛应用。但在光波波段,由于波长短引入的大电尺寸问题影响了相控阵的应用。本文提出了一种相控阵光学天线设计方法,通过增大阵列栅距大幅减少阵元数量,并通过设计阵元辐射特性抑制大栅距产生的栅瓣,显著增强相控阵光学天线的可实现性,该方法的代价为限制了天线的扫描范围。此外,还提出了通过模2π的方法降低光学移相器的实现难度,并论证了该方法在光波波段的合理性和可行性。

Phased-Array Antenna is widely applied in microwave band, which can form electrical controlled beam steering. But in light wave band, the extremely large electrical scale of the antenna makes it difficult to apply phased array. A design using much less dement by means of enlarging the grid distance of the array is described in this paper, which enhances the realizability of the optical phased-array antenna. Meanwhile, grating lobes caused by large grid distance is considered to be depressed by special design of the radiation pattern of the element. The price of this design is that the steering range is limited. Furthermore, a method to reduce the difficulty of phase-shifter is described also.