Fatemi Reza, Abiri Behrooz, Khachaturian Aroutin, Hajimiri Ali
Opt Express. 2018 Nov 12;26(23):29983-29999. doi: 10.1364/OE.26.029983.
Optical phased arrays (OPAs) on integrated photonic platforms provide a low-cost chip-scale solution for many applications. Despite the numerous demonstrations of OPA transmitters, the realization of a functional OPA receiver presents a challenge due to the low received signal level in the presence of noise and interference that necessitates high sensitivity of the receiver. In this paper, an integrated receiver system is presented that is capable of on-chip adaptive manipulation and processing of the captured waveform. The receiver includes an optoelectronic mixer that down-converts optical signals to radio frequencies while maintaining their phase and amplitude information. The optoelectronic mixer also provides conversion gain that enhances the system sensitivity and its robustness to noise and interference. Using this system, the first OPA receiver with a two-dimensional aperture of 8-by-8 receiving elements is demonstrated which can selectively receive light from 64 different angles. The OPA receiver can form reception beams with a beamwidth of 0.75 over an 8 grating-lobe-free field of view.
集成光子平台上的光学相控阵（OPAs）为许多应用提供了一种低成本的芯片级解决方案。尽管OPA发射器已有众多演示，但由于在存在噪声和干扰的情况下接收信号电平较低，这就要求接收器具有高灵敏度，因此实现一个功能齐全的OPA接收器仍面临挑战。本文提出了一种集成接收器系统，该系统能够对捕获的波形进行片上自适应操纵和处理。该接收器包括一个光电混频器，它将光信号下变频为射频信号，同时保持其相位和幅度信息。光电混频器还提供转换增益，提高了系统灵敏度及其对噪声和干扰的鲁棒性。利用该系统，展示了首个具有8×8接收元件二维孔径的OPA接收器，它可以从64个不同角度选择性地接收光。该OPA接收器可以在8个无光栅瓣的视场内形成波束宽度为0.75的接收波束。
