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Title: Phase-combining unit for aliasing suppression in an optical phased array

Integrated optical phased array (OPA) devices have been widely studied as a solution for solid-state light detection and ranging technology in the autonomous driving application. In this work, a phase-combining unit (PCU) is proposed and studied. With a given number (N) of phase shifters, instead of the generalN(phase shifters) toN(emitters) control, the PCU can enable anNto 2N–1 control, which efficiently suppresses the aliasing effect. The theoretical analysis, numerical simulation, and experimental proof-of-concept have been completed in this work. The results show that a maximum suppression of 92.54% can be achieved for the grating lobes in simulation, and an average 53.76% is tested for one grating lobe in the experiment. In conclusion, the PCU can be used as a universal aliasing suppression unit on many types of integrated OPA devices.

 
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NSF-PAR ID:
10368636
Author(s) / Creator(s):
; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
Volume:
47
Issue:
8
ISSN:
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 1996
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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