Miniaturized delay-enhanced substrate-guided wave based holograms for continuous tuning of delay times

In this paper, a miniaturized continuously tunable optical true-time-delay module has been designed, fabricated and evaluated for integrating into a X-band 4X4 2-D phased array antenna system. A novel symmetric structure is introduced to keep the output beam position fixed and avoid using a set of large collimators. This new structure is compact and easy to package while providing doubled delay time. Therefore, this module can easily scale up for large arrays due to its compressive structure.