Two-Dimensional Phased-Array Receiver Based on Integrated Silicon True Time Delay Lines

In this work, we first demonstrate a complete 2-D photonics-aided phased-array antenna (PAA) receiver with so far the largest scale of 8
$\times $
8 by utilizing highly integrated silicon true-time delay line chips. The prototype utilizes the wavelength-division-multiplexing technology to build the crucial optical beamforming network (OBFN) module so as to dramatically reduce the type and amount of silicon binary integrated optical time delay lines. The measured beam scanning range in the frequency range from 2 to 6 GHz is
$90^{\circ }\,\,\times \,\,90^{\circ }$
with a beam-pointing step of 1°. Furthermore, due to the online channelized signal processing module, we systematically characterize sensitivity, RF gain, and dynamic range of the photonics-aided PAA. Considering that we first utilize the photonic integration technology to realize a 2-D PAA demonstrator with the largest scale and the highest technological maturity, we believe that it presents a milestone in the development of future microwave photonics-based radar systems.