Patent ID: 11936782
Assignee: ARIZONA BOARD OF REGENTS ON BEHALF OF NORTHERN ARIZONA UNIVERSITY
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. An optical communication device, comprising:
a first photon detector configured to detect photons having a first wavelength and to signal polarization orientations of those photons and a first optical polarization controller coupled to the first optical detector;
a second photon detector configured to detect photons having a second wavelength and to signal polarization orientations of those photons and a second optical polarization controller coupled to the second optical detector;
an optical interface coupled to the first and second polarization controllers configured receive incoming photons representing a datastream and to maintain orientation of a polarization of a first incoming photon with respect to polarizations of subsequent incoming photons; and
a processor coupled to the first and second optical detectors and to the first and second polarization controllers, the processor configured to:
select a chosen measurement basis between first and second measurement bases for each incoming photon, each measurement basis defining a of pair mutually orthogonal polarization axes for the each of the first and second wavelengths;
configure the first and second polarization controllers such that the first and second optical detectors measure polarization with respect to the measurement basis selected for that photon;
perform a polarization measurement on each photon that determines a polarization axis of that photon in the measurement basis selected for that photon and a wavelength of that photon; and
decode the datastream using the wavelengths and polarizations of the incoming photon, including generating a signal indicating whether at least a portion of the datastream was altered;
wherein the first measurement basis defines, for each of the first and second wavelengths, a first polarization axis in a plane for that wavelength and a second polarization axis in that plane that is perpendicular to the first polarization axis for that wavelength;
wherein the second measurement basis defines, for each of the first and second wavelengths, a third polarization axis in the plane for that wavelength and a fourth polarization axis in the plane for that wavelength that is perpendicular to the third polarization axis for that wavelength; and
wherein the third and the fourth polarization axes for each wavelength are equally-weighted vector combinations of the first and second polarization axes for that wavelength.