Abstract

We explore the use of orbital-angular-momentum (OAM)-multiplexing to increase the capacity of free-space data transmission to moving platforms, with an added potential benefit of decreasing the probability of data intercept. Specifically, we experimentally demonstrate and characterize the performance of an OAM-multiplexed, free-space optical (FSO) communications link between a ground transmitter and a ground receiver via a moving unmanned-aerial-vehicle (UAV). We achieve a total capacity of 80 Gbit/s up to 100-m-roundtrip link by multiplexing 2 OAM beams, each carrying a 40-Gbit/s quadrature-phase-shift-keying (QPSK) signal. Moreover, we investigate for static, hovering, and moving conditions the effects of channel impairments, including: misalignments, propeller-induced airflows, power loss, intermodal crosstalk, and system bit error rate (BER). We find the following: (a) when the UAV hovers in the air, the power on the desired mode fluctuates by 2.1 dB, while the crosstalk to the other mode is −19 dB below the power on the desired mode; and (b) when the UAV moves in the air, the power fluctuation on the desired mode increases to 4.3 dB and the crosstalk to the other mode increases to −10 dB. Furthermore, the channel crosstalk decreases with an increase in OAM mode spacing.

Details

Title
High-Capacity Free-Space Optical Communications Between a Ground Transmitter and a Ground Receiver via a UAV Using Multiplexing of Multiple Orbital-Angular-Momentum Beams
Author
Long, Li 1   VIAFID ORCID Logo  ; Zhang, Runzhou 1 ; Zhao, Zhe 1 ; Xie, Guodong 1 ; Liao, Peicheng 1 ; Pang, Kai 1 ; Song, Haoqian 1 ; Liu, Cong 1 ; Ren, Yongxiong 1 ; Labroille, Guillaume 2 ; Pu Jian 2 ; Starodubov, Dmitry 1 ; Lynn, Brittany 3 ; Bock, Robert 4 ; Tur, Moshe 5 ; Willner, Alan E 1 

 Department of Electrical Engineering, U. of Southern California, Los Angeles, CA, USA 
 CAILabs Labs, Rennes, France 
 Space & Naval Warfare Systems Center, Pacific, San Diego, CA, USA 
 R-DEX Systems, Marietta, GA, USA 
 School of Electrical Engineering, Tel Aviv University, Ramat Aviv, Israel 
Pages
1-12
Publication year
2017
Publication date
Dec 2017
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1983426202
Copyright
© 2017. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.