Physical layer security in optical communications using Bessel modes

Patent metadata

Field	Value
Publication number	US-10291318-B2
Application number	US-201815964790-A
Country	US
Kind code	B2
Filing date	Apr 27, 2018
Priority date	Apr 27, 2017
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

Aspects of the present disclosure describe physical layer security in optical communications wherein Bessel modes are employed and significantly outperform conventional schemes with respect to secrecy and advantageously benefit from atmospheric turbulence effects with beam splitting attacks.

First claim

The invention claimed is:

1. An optical communications system comprising a free-space-optical (FSO) transmitter in optical communication with a FSO receiver, said system characterized by:
a physical-layer security (PLS) scheme employing Bessel modes;
a step-index multimode fiber (MMF) is used to generate the Bessel modes;

wherein the Bessel modes are solutions of a wave equation in a step-index MMF of core radius a, and the corresponding z-component of electric field in cylindrical coordinates (r,ϕ,z) can be represented as:
E z ( r,ϕ,z ) =AJ m ( k r r ) e jmϕ e jβz ,r≤a;
where β is the propagation constant, J m (⋅) is the Bessel function of the m-th order, and k r is defined as k r =√{square root over (n core 2 k 0 2 −β 2 )}, with k 0 =2π/λ being the free space wave number and n core being refractive index of the core.

2. The system according to claim 1 further characterized in that graded-index MMFs are used to generate the Bessel modes.

3. The system according to claim 1 further characterized in that multidimensional signaling is employed wherein the Bessel modes are used as basis functions.

Assignees

• Nec Lab America Inc
• Nec Corp

Inventors

• Djordjevic Ivan
• Zhang Shaoliang
• Wang Ting

Classifications

• H04L63/08

  for authentication of entities (cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32) · CPC title

• H03M13/1102

  Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes · CPC title

• H04J14/04

  Mode multiplex systems · CPC title

• H04B10/11

  Arrangements specific to free-space transmission, i.e. transmission through air or vacuum · CPC title

• H04B10/2581

  Multimode transmission · CPC title