Private free-space communication.

grarpamp grarpamp at
Wed Jul 7 22:01:14 PDT 2021


Seems more for distances shorter than a simple
cable run to the next house or business parcel.
The non-RF part is nice, but still... TEMPEST.
And military marketing means consumer priced
out, but worth inquiring.

Optics/RF are more for where you can't run fiber/copper,
can't run fiber/copper cheaply, need unique range or altitude
solutions, need to be transient or discreet, or diversity
in hop tech, etc.

Perhaps point is, in a p2p meshnet, reliability and speed
of fiber/copper come first choice.


> i am having trouble finding more detail on this system

China's researchers are working on some cool stuff,
try writing her to ask for a list of papers, request
ones of interest, and links to their favorite hopefully
open paper repos...

zhanyueying at  Yueying Zhan
Key Laboratory of Space Utilization,
Technology and Engineering Center for Space Utilization,
Chinese Academy of Sciences,
Beijing 100094, China

Proceedings Article | 17 April 2020 Paper
1.12Tbit/s (10x112Gbit/s) coherent free space optical communication
using DP-QPSK and WDM technology
Ziyuan Shi, Yueying Zhan, Jian Xiong
Proc. SPIE. 11455, Sixth Symposium on Novel Optoelectronic Detection
Technology and Applications
KEYWORDS: Transmitters, Modulation, Polarization, Wavelength division
multiplexing, Receivers, Telecommunications, Free space optics, Dense
wavelength division multiplexing, Free space optical communications
A 1.12Tb/s FSO communication system with WDM and DP-QPSK is proposed.
The performances of the system in case of sunny, rainy, foggy under
50GHz, 100GHz and 200GHz channel spacing are simulated and analyzed.

SPIE Journal Paper | 1 August 2016
Optical encryption of parallel quadrature phase shift keying signals
based on nondegenerate four-wave mixing in highly nonlinear fiber
Yue Cui, Min Zhang, Yueying Zhan, Danshi Wang, Shanguo Huang
OE Vol. 55 Issue 08
KEYWORDS: Phase shift keying, Modulation, Nonlinear optics, Four wave
mixing, Optical networks, Signal processing, Computer security,
Optical engineering, Network security, Optical communications
A scheme for optical parallel encryption/decryption of quadrature
phase shift keying (QPSK) signals is proposed, in which three QPSK
signals at 10  Gb/s are encrypted and decrypted simultaneously in the
optical domain through nondegenerate four-wave mixing in a highly
nonlinear fiber. The results of theoretical analysis and simulations
show that the scheme can perform high-speed wiretapping against the
encryption of parallel signals and receiver sensitivities of encrypted
signal and the decrypted signal are −25.9 and −23.8  dBm,
respectively, at the forward error correction threshold. The results
are useful for designing high-speed encryption/decryption of advanced
modulated signals and thus enhancing the physical layer security of
optical networks.

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