NTRS - NASA Technical Reports Server

Back to Results
Single-mode Fiber and Few-Mode Fiber Photonic Lanterns Performance Evaluated for Use in a Scalable Real-Time Photon Counting Ground ReceiverPhotonic lanterns provide an efficient way of coupling light from a single large-core fiber to multiple small-core fibers. This capability is of interest for space to ground communication applications. In these applications, the optical ground receivers require high-efficiency coupling from an atmospherically distorted focus spot to multiple fiber coupled single pixel super-conducting nanowire detectors. This paper will explore the use of photonic lanterns in a real-time ground receiver that is scalable and constructed with commercial parts. The number of small-core fibers that make a photonic lantern determines the number of spatial modes that they couple. For instance, lanterns made with n number of single-mode fibers can couple n number of spatial modes. Although the laser transmitted from a spacecraft originates as a Gaussian shape, the atmosphere distorts the beam profile by scattering energy into higher-order spatial modes. Therefore, if a ground receiver is sized for a target data rate with n number of detectors, the corresponding lantern made with single-mode fibers will couple n number of spatial modes. The energy of the transmitted beam scattered into spatial modes higher than n will be lost. This paper shows this loss may be reduced by making lanterns with few-mode fibers instead of single-mode fibers, increasing the number of spatial modes that can be coupled and therefore increasing the coupling efficiency to single pixel, single photon detectors. The free space to fiber coupling efficiency of these two types of photonic lanterns are compared over a range of the free-space coupling numerical apertures and mode field diameters. Results indicate the few mode fiber lantern has higher coupling efficiency for telescopes with longer focal lengths under higher turbulent conditions. Also presented is analysis of the jitter added to the system by the lanterns, showing the few-mode fiber photonic lantern adds more jitter than the single-mode fiber lantern, but less than a multimode fiber.
Document ID
Document Type
Conference Paper
External Source(s)
Tedder, Sarah A.
(NASA Glenn Research Center Cleveland, OH, United States)
Vyhnalek, Brian E.
(NASA Glenn Research Center Cleveland, OH, United States)
Leon-Saval, Sergio
(University of Sydney Sydney, Australia)
Betters, Christopher
(University of Sydney Sydney, Australia)
Floyd, Bert
(HX5 Sierra, LLC Cleveland, OH, United States)
Staffa, Jeremy
(Rochester Univ. Rochester, NY, United States)
Lafon, Robert
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
May 20, 2019
Publication Date
March 4, 2019
Publication Information
Publication: Proceedings of SPIE, Free-Space Laser Communications XXXI
Volume: 10910
ISSN: 0277-786X
Subject Category
Report/Patent Number
Meeting Information
SPIE LASE(San Francisco, CA)
Funding Number(s)
WBS: 277985.
Distribution Limits
Public Use Permitted.
Technical Review
Single Expert
photon counting
ground receiver
fiber coupling
photonic lanterns
No Preview Available