Switched optical network

Claim 2

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signals from two or more transmitter stations to provide optically multiplexed channels corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optical multiplexer for selecting any one of the channels comprising the optical multiplexing means for reception at the receiver and responsive to a selection signal to output one transmitter station signal to the corresponding respective receiver station; and an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed channels to any one of the demultiplexing means.

Claim 3

A network as claimed in claim 1 in which each multiplexing means includes a plurality of optical sources for providing power at two or more wavelengths, a plurality of modulators, each modulator being optically coupled to one of the optical sources and being responsive to the signals from a transmitter station to provide an optical signal representative of that transmitter station signal, and a plurality of optical combiners for combining the optical signals to form the optical multiplexer.

Claim 4

A network as claimed in claim 2 in which there is only one optical source of optical power at each wavelength.

Claim 5

A network as claimed in claim 2 in which the wavelengths of the optical sources are fixed by a central wavelength referencing means.

Claim 6

A network as claimed in claim 2 in which the optical sources are lasers.

Claim 7

A network as claimed in claim 2 including a plurality of distinct units for housing the modulators and in which each modulator of the network which is coupled to an optical source of a given wavelength is housed in the same unit.

Claim 8

A network as claimed in claim 6 in which the number of modulators in each unit is equal to the number of optically multiplexed channels.

Claim 9

A network as claimed in claim 2 including a plurality of distinct units for housing the modulators and in which all the modulators of the network whose optical outputs form part of the same multiplexer are housed in the same unit.

Claim 10

A network as claimed in claim 8 in which the number of units is equal to the number of distinct wavelengths from the optical sources.

Claim 11

A network as claimed in claim 8 in which the modulators of each unit are formed on a single lithium niobate substrate.

Claim 12

A network as claimed in claim 1 in which the optical switch means includes a plurality of optical space switches, each having one input optically coupled to a respective multiplexing means, and a plurality of outputs, each demultiplexer being optically coupled to one output of every optical space switch.

Claim 13

A network as claimed in claim 1 in which the optical switch means includes a plurality of optical space switches, each having a plurality of inputs, each multiplexing means being optically coupled to an input of every optical space switch, and each having a plurality of outputs, each demultiplexer being optically coupled to a distinct output of an optical space switch.

Claim 14

A network as claimed in claim 12 in which the number of outputs of each optical space switch equals the number of multiplexed channels.

Claim 15

A network as claimed in claim 13 in which each optical multiplexing means is a star coupler having a plurality of outputs, each output being optically coupled to an input of a distinct optical space switch.

Claim 16

A network as claimed in claim 2 in which each demultiplexer is also coupleable to any one of said optical sources by a selection means responsive to the selection signal.

Claim 17

A network as claimed in claim 15, in which the selection means comprises a plurality of secondary optical space switches equal in number to the number of optical space switches, each having a plurality of inputs equal in number to the number of distinct wavelengths of the optical sources and each input being connected to an optical source of distinct wavelength, and each having a plurality of outputs equal in number to the number of optical space switches, each output of a given secondary optical space switch being combined with a distinct output of one corresponding optical space switch.

Claim 18

A network as claimed in claim 16 in which each secondary optical space switch forms part of the corresponding optical space switch, each output of the optical space switch being optically coupleable simultaneously to one of the inputs connected to a multiplexer and to one of the inputs connected to an optical source.

Claim 19

A network as claimed in claim 15 for use with a heterodyne receiver, in which the selection means includes a frequency shift means whereby each optical source is frequency shifted by a predetermined amount prior to being coupled with the output of an optical space switch.

Claim 20

A network as claimed in claim 2 in which each receiver station includes an optical detector and a tunable filter, the tunable filter being responsive to a said selection signal to permit only one wavelength of an optical multiplexer coupled to the receiver station to reach the optical detector.

Claim 21

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signal from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optical multiplexer and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means, wherein said optical switch means includes a plurality of optical space switches, each having one input optically coupled to a respective multiplexing means, and a plurality of outputs, each demultiplexer being optically coupled to one output of every optical space switch.

Claim 22

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signal from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optical multiplexer and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means, wherein said optical switch means includes a plurality of optical space switches, each having one input optically coupled to a respective multiplexing means, and a plurality of outputs, each demultiplexer being optically coupled to one output of every optical space switch.

Claim 23

A network as claimed in claim 20 in which each multiplexing means includes a plurality of optical sources for providing power at two or more wavelengths, a plurality of modulators, each modulator being optically coupled to one of the optical sources and being responsive to the signals from a transmitter station to provide an optical signal representative of that transmitter station signal, and a plurality of optical combiners for combining the optical signals to form the optical multiplexer.

Claim 24

A network as claimed in claim 21 in which each demultiplexer is also coupleable to any one of said optical sources by a selection means responsive to the selection signal.

Claim 25

A network as claimed in claim 22 in which the selection means comprises a plurality of secondary optical space switches equal in number to the number of optical space switches, each having a plurality of inputs equal in number to the number of distinct wavelengths of the optical sources and each input being connected to an optical source of distinct wavelength, and each having a plurality of outputs equal in number to the number of optical space switches, each output of a given secondary optical space switch being combined with a distinct output of one corresponding optical space switch.

Claim 26

A network as claimed in claim 23 in which each secondary optical space switch forms part of the corresponding optical space switch, each output of the optical space switch being optically coupleable simultaneously to one of the inputs connected to a multiplexer and to one of the inputs connected to an optical source.

Claim 27

A network as claimed in claim 22 for use with a heterodyne receiver, in which the selection means includes a frequency shift means whereby each optical source is frequency shifted by a predetermined amount prior to being coupled with the output of an optical space switch.

Claim 28

A network as claimed in claim 20 in which each receiver station includes an optical detector and a tunable filter, the tunable filter being responsive to said selection signal to permit only one wavelength of the optically multiplexed signals coupled to the receiver station to reach the optical detector.

Claim 29

A network as claimed in claim 21 in which there is only one optical source of optical power at each wavelength.

Claim 30

A network as claimed in claim 21 in which the wavelengths of the optical sources are fixed by a central wavelength referencing means.

Claim 31

A network as claimed in claim 21 in which the optical sources are lasers.

Claim 32

A network as claimed in claim 21 including a plurality of distinct units for housing the modulators and in which each modulator of the network which is coupled to an optical source of a given wavelength is housed in the same unit.

Claim 33

A network as claimed in claim 30 in which the number of modulators in each unit is equal to the number of optically multiplexed signals.

Claim 34

A network as claimed in claim 21 including a plurality of distinct units for housing the modulators and in which all the modulators of the network whose optical outputs form part of the same multiplexer are housed in the same unit.

Claim 35

A network as claimed in claim 32 in which the number of units is equal to the number of distinct wavelengths from the optical sources.

Claim 36

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signals from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optically multiplexed signal and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means, wherein said optical switch means includes a plurality of optical space switches, each having a plurality of inputs, each multiplexing means being optically coupled to an input of every optical space switch, and each having a plurality of outputs, each demultiplexer being optically coupled to a distinct output of an optical space switch.

Claim 37

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signals from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optically multiplexed signal and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means, wherein said optical switch means includes a plurality of optical space switches, each having a plurality of inputs, each multiplexing means being optically coupled to an input of every optical space switch, and each having a plurality of outputs, each demultiplexer being optically coupled to a distinct output of an optical space switch.

Claim 38

A network as claimed in claim 34 in which the number of outputs of each optical space switch equals the number of optically multiplexed signals.

Claim 39

A network as claimed in claim 35 in which each optical multiplexing means is a star coupler having a plurality of outputs, each output being optically coupled to an input of a distinct optical space switch.

Claim 40

A network as claimed in claim 34 in which each multiplexing means includes a plurality of optical sources for providing power at two or more wavelengths, a plurality of modulators, each modulator being optically coupled to one of the optical sources and being responsive to the signals from a transmitter station to provide an optical signal representative of that transmitter station signal, and a plurality of optical combiners for combining the optical signals to form the optical multiplexer.

Claim 41

A network as claimed in claim 37 in which each demultiplexer is also coupleable to any one of said optical sources by a selection means responsive to the selection signal.

Claim 42

A network as claimed in claim 38 in which the selection means comprises a plurality of secondary optical space switches equal in number to the number of optical space switches, each having a plurality of inputs equal in number to the number of distinct wavelengths of the optical sources and each input being connected to an optical source of distinct wavelength, and each having a plurality of outputs equal in number to the number of optical space switches, each output of a given secondary optical space switch being combined with a distinct output of one corresponding optical space switch.

Claim 43

A network as claimed in claim 39 in which each secondary optical space switch forms part of the corresponding optical space switch, each output of the optical space switch being optically coupleable simultaneously to one of the inputs connected to a multiplexer and to one of the inputs connected to an optical source.

Claim 44

A network as claimed in claim 38 for use with a heterodyne receiver, in which the selection means includes a frequency shift means whereby each optical source is frequency shifted by a predetermined amount prior to being coupled with the output of an optical space switch.

Claim 45

A network as claimed in claim 37 in which each receiver station includes an optical detector and a tunable filter, the tunable filter being responsive to said selection signal to permit only one wavelength of an optical multiplexer coupled to the receiver station to reach the optical detector.

Claim 46

A network as claimed in claim 37 in which there is only one optical source of optical power at each wavelength.

Claim 47

A network as claimed in claim 37 in which the wavelengths of the optical sources are fixed by a central wavelength referencing means.

Claim 48

A network as claimed in claim 37 in which the optical sources are lasers.

Claim 49

A network as claimed in claim 37 including a plurality of distinct units for housing the modulators and in which each modulator of the network which is coupled to an optical source of a given wavelength is housed in the same unit.

Claim 50

A network as claimed in claim 46 in which the number of modulators in each unit is equal to the number of optically multiplexed signals.

Claim 51

A network as claimed in claim 37 including a plurality of distinct units for housing the modulators and in which all the modulators of the network whose optical outputs form part of the same multiplexer are housed in the same unit.

Claim 52

A network as claimed in claim 48 in which the number of units is equal to the number of distinct wavelengths from the optical sources.

Claim 53

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signals from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optically multiplexed signal and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means; each said multiplexing means includes a plurality of optical sources for providing power at two or more wavelengths, a plurality of modulators, each modulator being optically coupled to one of the optical sources and being responsive to the signals from a transmitter station to provide an optical signal representative of that transmitter station signal, and a plurality of optical combiners for combining the optical signals to form the optically multiplexed signals; a plurality of distinct units for housing said modulators such that all the modulators of the network whose optical outputs form part of the same multiplexer are housed in the same unit, wherein the number of units is equal to the number of distinct wavelengths from the optical sources; and the modulators of each unit are formed on a single lithium niobate substrate.

Claim 54

A switched optical network for connecting signals from any one of a plurality of transmitter stations with any one of a plurality of receiver stations comprising: at least two optical multiplexing means each responsive to signals from two or more transmitter stations to provide optically multiplexed signals corresponding to the transmitter station signals; a plurality of optical demultiplexing means each associated with a respective receiver and each responsive to an optically multiplexed signal and a selection signal to output one transmitter station signal to the corresponding respective receiver station; an optical switch means responsive to switch signals to optically couple any one of the optically multiplexed signals to any one of the demultiplexing means; each said multiplexing means includes a plurality of optical sources for providing power at two or more wavelengths, a plurality of modulators, each modulator being optically coupled to one of the optical sources and being responsive to the signals from a transmitter station to provide an optical signal representative of that transmitter station signal, and a plurality of optical combiners for combining the optical signals to form the optically multiplexed signals; a plurality of distinct units for housing said modulators such that all the modulators of the network whose optical outputs form part of the same multiplexer are housed in the same unit, wherein the number of units is equal to the number of distinct wavelengths from the optical sources; and the modulators of each unit are formed on a single lithium niobate substrate.