公开(公告)号：US20160057514A1

公开(公告)日：2016-02-25

申请号：US14780948

申请日：2014-03-12

Applicant: BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY

Inventor： Andrew LORD

IPC: H04Q11/00 ,  H04J14/02

CPC classification number: H04Q11/0005 ,  H04J14/0204 ,  H04J14/0205 ,  H04J14/0217 ,  H04J14/0219 ,  H04Q2011/0015 ,  H04Q2011/0058

Abstract: An optical switch suitable for use in a ROADM of an optical network node having one or more optical fiber per direction, the fibers together carrying optical signals comprising up to N independent wavelength channels, is disclosed. The switch includes an Optical Cross-Connect (OXC) having F1 input ports and F2 output ports. At least one optical splitter, at least one optical combiner and at least two wavelength blockers are separately connected to the OXC, the input and output parts thereof defining ports of the OXC. The OXC is controllable to switch optical signals arriving at any of the F1 switch input ports to any of the F2 switch output ports via one or more of the optical splitters, wavelength blockers and/or optical combiners. A method for switching optical signals is also disclosed.

Abstract translation: 公开了一种适用于每个方向具有一个或多个光纤的光网络节点的ROADM的光开关，所述光纤一起承载包括多达N个独立波长信道的光信号。 交换机包括具有F1输入端口和F2输出端口的光交叉连接（OXC）。 至少一个光分路器，至少一个光合成器和至少两个波长阻挡器分别连接到OXC，其输入和输出部分限定OXC的端口。 OXC可控制，以通过一个或多个光分路器，波长阻挡器和/或光学组合器将到达任何F1开关输入端口的光信号切换到任何F2开关输出端口。 还公开了一种用于切换光信号的方法。

公开(公告)号：US20240348431A1

公开(公告)日：2024-10-17

申请号：US18579796

申请日：2022-07-13

Applicant: BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY

Inventor： Andrew LORD

IPC: H04L9/08

CPC classification number: H04L9/0852 ,  H04L9/0819 ,  H04L9/0838

Abstract: A method of performing Quantum Key Distribution can include quantum transmission in a first basis state and in a second basis state being non-orthogonal to the first basis state, from a quantum transmission apparatus to a quantum receiving apparatus over two pairs of optical channels, wherein transmitting in the first basis state includes, at a first time slot, transmitting a photon over a first channel of the first pair and transmitting no photon over a second channel of the first pair, and, at a subsequent time slot, transmitting a photon over the first channel of the first pair, and transmitting a photon over the second channel of the first pair, wherein transmission in the second basis state includes transmitting a first portion of a probability distribution of a photon from the quantum transmission apparatus to the quantum receiving apparatus; and transmitting a second portion of a probability distribution of the photon from the quantum transmission apparatus to the quantum receiving apparatus.

公开(公告)号：US20240072853A1

公开(公告)日：2024-02-29

申请号：US18261707

申请日：2021-12-17

Applicant: BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY

Inventor： Andrew LORD ,  Anas AL RAWI ,  Neil PARKIN

IPC: H04B7/0456

CPC classification number: H04B7/0456

Abstract: A method of transmitting precoded signals can include precoding an optical signal to produce a precoded optical signal, transmitting a precoded optical signal over an optical portion of a first transmission channel, converting the precoded optical signal to a first MIMO signal, transmitting the first MIMO signal over a wireless portion of the first transmission channel, transmitting the precoded optical signal over an optical portion of a second transmission channel, converting the precoded optical signal to a second MIMO signal; transmitting the second MIMO signal over a wireless portion of the second transmission channel; wherein the precoding takes account of both first channel state information associated with the first transmission channel and second channel state information associated with the second transmission channel.

公开(公告)号：US20220376905A1

公开(公告)日：2022-11-24

申请号：US17753772

申请日：2020-08-18

Applicant: British Telecommunications Public Limited Company

Inventor： Andrew LORD

IPC: H04L9/08

Abstract: There is herein disclosed a method of communication between a client pair, the client pair including an upstream client and a downstream client, the method being performed over a first optical fiber in an optical fiber pair and including: transmitting a downstream DWDM signal over the first optical fiber, wherein the downstream DWDM signal has a first frequency and contains first data originating from the upstream client, transmitting an upstream DWDM signal over the first optical fiber, wherein the upstream DWDM signal has a second frequency and contains second data originating from the downstream client, wherein the first frequency is different to the second frequency, and performing Quantum Key Distribution over the second optical fiber of the optical fiber pair.

公开(公告)号：US20220173895A1

公开(公告)日：2022-06-02

申请号：US17593684

申请日：2020-03-11

Applicant: BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY

Inventor： Andrew LORD

IPC: H04L9/08 ,  H04B10/70

Abstract: There is herein disclosed a system for performing Quantum Key Distribution, the system including a transmitter adapted to transmit a plurality of optical pulses, a first receiver, a second receiver, an optical switch with an input which is in optical communication with the transmitter, the switch being switchable between a first switching position in which the input is optically connected to the first receiver, and a second switching position in which the input is optically connected to the second receiver, the system further including a guide for guiding a portion of the plurality of optical pulses to the first receiver via an optical path that bypasses the optical switch.

公开(公告)号：US20200350995A1

公开(公告)日：2020-11-05

申请号：US15733354

申请日：2018-12-13

Applicant: British Telecommunications Public Limited Company

Inventor： Andrew LORD

IPC: H04B10/70 ,  H04J14/02 ,  H04B10/50 ,  H04B10/66 ,  H04L9/08

Abstract: An optical data transmission system and method for, at an optical transmitter, converting to a second wavelength, an optical data signal at a first wavelength; transmitting at the second wavelength, the optical data signal to an optical receiver over an optical path; and transmitting at the first wavelength, to the receiver over the path a single-photon signal comprising a stream of single photons. The optical path is configured to carry optical signals at different wavelengths and the optical path attenuates signals at the first wavelength less than the optical path attenuates signals at the second wavelength. The optical data transmission system and method for, at the receiver, receiving the single-photon signal at the first wavelength and receiving the optical data signal at the second wavelength; and converting the optical data signal to the first wavelength for detection.