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Examining the Ability of an FSO Receiver to Simultaneously Communicate with Multiple TransmittersFSO (Free-Space Optical)-based communication systems experience difficulty with receiving and separating signals arising from multiple transmitters, a capability that would facilitate implementation of MIMO (Multiple-In, Multiple-Out) systems. Current implementations require multiple, distinct optical antennas, each tracking a single user, which proves bulky and costly, especially if the transmitters are moving and must be tracked. A fiber-bundle receiver has the potential to use multiple pathways, corresponding to the individual fibers within the receiver, to capture different combinations of the incoming optical signals. If the bundle provides linear combining of the optical signals from both the individual fibers in the bundle and amongst the incoming optical signals, signal processing could extract the individual signals from the combinations. In this paper, we experimentally investigate whether the fiber-bundle receiver possesses sufficient linearity of operation to allow the separation of two signals by simple processing algorithms, for both turbulent and non-turbulent conditions. Data from two distinct sources enters a single-bundle, single field of view receiver, and a basis signal from one transmitter provides the reference for performing simple subtraction-based extraction of the unknown signal from the other transmitter. The experimental results show that the receiver does operate linearly, and that the linear operation remains sufficiently intact in the presence of turbulence to extract a recognizable copy of one signal from the other. The ability of the fiber bundle receiver to mitigate turbulence effects appears to assist in maintaining this sufficient level of linearity.
Document ID
Document Type
Conference Paper
LoPresti, Peter G.
(Tulsa Univ. OK, United States)
Suddath, Shannon
(Tulsa Univ. OK, United States)
Refai, Hazem
(Oklahoma State Univ. Tulsa, OK, United States)
Tedder, Sarah A.
(NASA Glenn Research Center Cleveland, OH, United States)
Schoenholz, Bryan L.
(NASA Glenn Research Center Cleveland, OH, United States)
Date Acquired
August 27, 2018
Publication Date
January 27, 2018
Subject Category
Communications And Radar
Report/Patent Number
Meeting Information
SPIE Photonics West(San Francisco, CA)
Funding Number(s)
WBS: WBS 405034.
Distribution Limits
Public Use Permitted.
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