Silicon photonic receiver for satellite laser communication terminals

Abstract

We report the optical performance of a photonic receiver for laser communication applications. The receiver is composed of 14 x 12 grating coupler arrays. The received optical signal power will be combined electrically via germanium photodi-odes. The photonic receiver is designed for 20-mu m to 30-mu m mode field diameter (MFD) input sources. To maximize the fill factor of the 200 mu m x 200 mu m light-receiving area, a design strategy has been proposed. (1) Grating couplers are customized for compactness. (2) Periods of grating couplers are designed to work as end-fire and back-fire grating cou-plers for the same incident angle of the input laser source. (3) Different widths of waveguides are routed to minimize cross talk. The photonic receiver is evaluated with a 10-mu m MFD source. As a result of the evaluation, the receiving area considering the minimum efficiency of -10.5 dB is 95% of the designed area when illuminating 20-mu m to 300-mu m MFD laser sources.(c) 2022 Optica Publishing Group