Optical switching system

Claim 2

An optical switching system characterized in that there are provided: first means (600-1 - 600-n) for receiving an input optical signal which is a wavelength-division multiplexed and time-division multiplexed signal, said first means including first separating means for separating and outputting a time-division multiplexed signal component of the input optical signal in each of divided wavelengths and second separating means for separating a control information included in the input optical signal; second means (730-1 - 730-m) coupled to said first means for storing an optical signal output from said first means for every time slot identical to that used for the separation in said first means and for reading out stored optical signals successively in a sequence of predetermined time slots so as to convert wavelengths of the optical signals into predetermined wavelengths; third means (750-1 - 750-m) coupled to said second means for multiplexing wavelengths of optical signals output from said second means into wavelength-division multiplexed optical signals and for delaying a phase of the wavelength-division multiplexed optical signals a predetermined quantity; an optical data bus (800) coupled to said third means for receiving optical signals output from said third means and for transferring the optical signals in a predetermined direction within said optical data bus; fourth means (850-1 - 850-m) coupled to said optical data bus for extracting optical signals having wavelengths belonging to predetermined wavelength regions from said optical data bus and delaying a phase of the extracted optical signals a predetermined quantity and for converting wavelengths of the extracted optical signals into predetermined wavelengths; and fifth means (950-1 - 950-n) coupled to said fourth means for multiplexing the wavelengths of the optical signals output from said fourth means so as to output an output optical signal which is a wavelength-division multiplexed and time-division multiplexed signal.

Claim 3

The optical switching system as claimed in claim 1, characterized in that said first separating means of said first means (600-1 - 600-n) comprises a frequency divider (60-1, 60-2) and said second separating means of said first means comprises a detector (65-1 - 65-3, 66-1 - 66-3) for detecting the control information included in the input optical signal and for outputting the input optical signal.

Claim 4

The optical switching system as claimed in claim 1 or 2, characterized in that said second means (730-1 - 730-m) comprises for each optical signal output from said first means (600-1 - 600-n) a time-division multiplexed signal separator (72) for separating time-­division multiplexed optical signals from the optical signal output from said first means, optical memories (73-1 - 73-100) for storing the time-division multiplexed optical signals or optical packet output from said time-division multiplexed signal separator during mutually different time slots, and a frequency shifter (74-1 - 74-100) for converting into the predetermined wavelengths the wavelengths of the optical signals which are read out from said optical memories based on said control information.

Claim 5

The optical switching system as claimed in any of claims 1 to 3, characterized in that said third means (750-1 - 750-m) comprises a wavelength multiplexer (75) for multiplexing the optical signals output from said second means (730-1 - 730-m) into a wavelength-­division multiplexed optical signal, and an optical delay circuit (76) for delaying the phase of the wavelength-division multiplexed optical signal the predetermined quantity.

Claim 6

The optical switching system as claimed in claim 4, characterized in that said third means (750-1 - 750-m) further comprises for each wavelength-division multiplexed optical signal output from said optical delay circuit (76) an optical coupler (77-1 - 77-3, 78-1 - 78-3) for optically coupling said optical delay circuit to said optical data bus (800).

Claim 7

The optical switching system as claimed in any of claims 1 to 5, characterized in that said optical data bus (800) comprises a loop shaped optical fiber.

Claim 8

The optical switching system as claimed in any of claims 1 to 6, characterized in that said fourth means (850-1 - 850-m) comprises an optical bandpass filter (81-1 - 81-3, 82-1 - 82-3) for extracting the optical signals having the wavelengths belonging to the predetermined wavelength regions from said optical data bus (800).

Claim 9

The optical switching system as claimed in claim 7, characterized in that said fourth means (850-1 - 850-m) further comprises an optical delay circuit (85-1 - 85-3, 86-1 - 86-3) for delaying the phase of the extracted optical signals the predetermined quantity, and a frequency shifter (90-1 - 90-3, 91-1 - 91-3) for converting the wavelengths of the extracted optical signals output from said optical delay circuit into the predetermined wavelengths.

Claim 10

The optical switching system as claimed in any of claims 1 to 8, characterized in that said control information contains at least an information selected from a group including a wavelength information of the optical input signal, a content information, a wavelength information of the optical output signal, an output channel information, an information quantity, a priority information, and a time slot information.

Claim 11

The optical switching system as claimed in any of claims 1 to 9, characterized in that said input optical signal is made up of cells having a fixed length and a header which includes a routing information, said routing information comprising a number a of output optical fibers which are coupled to an output side of said fifth means, an optical frequency b and an output time slot c.

Claim 12

The optical switching system as claimed in claim 10, characterized in that said second means (730-1 - 730-m) converts the wavelengths of all the stored optical signals depending on values of the routing information (a, b, c).

Claim 13

The optical switching system as claimed in claim 11, characterized in that said second means (730-1 - 730-m) converts optical frequencies of all the stored optical signals to an optical frequency abc.

Claim 14

The optical switching system as claimed in any of claims 1 to 12, characterized in that said first through fifth means process optical signals by an all-optical processing.

Claim 15

An optical switching system characterized in that there are provided: a plurality of detecting means (100-1 - 100-n) for receiving an input optical signal which is a wavelength-division multiplexed signal and for detecting a control information included in the input optical signal; a plurality of first optical buses (150-1 - 150-m) coupled to said detecting means for transferring optical signals output from said detecting means in a predetermined direction within the respective first optical data buses; a plurality of optical bandpass filters (130-1 - 130-n) coupled to each of said first optical data buses for extracting optical signals in predetermined wavelength regions based on said control information; control information detecting means (330-1 - 330-n) coupled to said optical bandpass filters for detecting a control information included in the optical signals output from said optical bandpass filters; first shift means (360-1 - 360-n) coupled to said optical bandpass filters for delaying phases of the optical signals output from said optical bandpass filters by a predetermined quantity and for shifting wavelengths of the optical signals a predetermined quantity determined by the control information output from said control information detecting means; switching means (390-1 - 390-n) coupled to said first shift means for outputting the optical signals output from said first shift means to one of first paths and second paths responsive to the control information output from said control information detecting means; a second optical data bus (410) coupled to the first path of said switching means for transferring the optical signals output from said switching means in a predetermined direction within said second optical data bus; shift and delay means (220-1 - 220-n) coupled to the second path of said switching means for receiving predetermined wavelength components of the optical signals output from said switching means determined by the control information output from said control information detecting means and for shifting wavelengths and delaying the predetermined wavelength components, said shift and delay means outputting optical signals corresponding to the shifted and delayed predetermined wavelength components to the respective first optical data buses; second shift means (510-1 - 510-n) coupled to said second optical data bus for extracting extracting optical signals having wavelengths belonging to predetermined wavelength regions from said second optical data bus and for shifting wavelengths of the extracted optical signals a predetermined quantity determined by the control information output from said control information detecting means; and multiplexing means (550-1 - 550-p) coupled to said second shift means for multiplexing the wavelengths of the optical signals output from said fourth means so as to output an output optical signal which is a wavelength-division multiplexed.

Claim 16

An optical switching system characterized in that there are provided: a plurality of detecting means (100-1 - 100-n) for receiving an input optical signal which is a wavelength-division multiplexed signal and for detecting a control information included in the input optical signal; a plurality of first optical buses (150-1 - 150-m) coupled to said detecting means for transferring optical signals output from said detecting means in a predetermined direction within the respective first optical data buses; a plurality of optical bandpass filters (130-1 - 130-n) coupled to each of said first optical data buses for extracting optical signals in predetermined wavelength regions based on said control information; control information detecting means (330-1 - 330-n) coupled to said optical bandpass filters for detecting a control information included in the optical signals output from said optical bandpass filters; first shift means (360-1 - 360-n) coupled to said optical bandpass filters for delaying phases of the optical signals output from said optical bandpass filters by a predetermined quantity and for shifting wavelengths of the optical signals a predetermined quantity determined by the control information output from said control information detecting means; switching means (390-1 - 390-n) coupled to said first shift means for outputting the optical signals output from said first shift means to one of first paths and second paths responsive to the control information output from said control information detecting means; a second optical data bus (410) coupled to the first path of said switching means for transferring the optical signals output from said switching means in a predetermined direction within said second optical data bus; shift and delay means (220-1 - 220-n) coupled to the second path of said switching means for receiving predetermined wavelength components of the optical signals output from said switching means determined by the control information output from said control information detecting means and for shifting wavelengths and delaying the predetermined wavelength components, said shift and delay means outputting optical signals corresponding to the shifted and delayed predetermined wavelength components to the respective first optical data buses; second shift means (510-1 - 510-n) coupled to said second optical data bus for extracting extracting optical signals having wavelengths belonging to predetermined wavelength regions from said second optical data bus and for shifting wavelengths of the extracted optical signals a predetermined quantity determined by the control information output from said control information detecting means; and multiplexing means (550-1 - 550-p) coupled to said second shift means for multiplexing the wavelengths of the optical signals output from said fourth means so as to output an output optical signal which is a wavelength-division multiplexed.

Claim 17

The optical switching system as claimed in claim 14, characterized in that said detecting means (100-1 - 100-n) includes an optical coupler (11-1 - 11-5) which optically couples said detecting means to a corresponding one of said first optical data buses (150-1 - 150-m).

Claim 18

The optical switching system as claimed in claim 14 or 15, characterized in that said first optical data buses (150-1 - 150-m) respectively comprise a loop shaped optical fiber.

Claim 19

The optical switching system as claimed in claim 16, characterized in that said first optical data buses (150-1 - 150-m) respectively have an optical bandpass filter (15-1 - 15-10) inserted at a predetermined position of the loop.

Claim 20

The optical switching system as claimed in claim 16 or 17, characterized in that said first optical data buses (150-1 - 150-m) respectively have an optical amplifier (12) inserted at a predetermined position of the loop.

Claim 21

The optical switching system as claimed in any of claims 14 to 18, characterized in that said second optical data bus (410) comprises a loop shaped optical fiber.

Claim 22

The optical switching system as claimed in any of claims 14 to 19, characterized in that said switching means (390-1 - 390-n) includes an optical coupler (40-1) which optically couples said switching means to said second optical data bus (410).

Claim 23

The optical switching system as claimed in any of claims 14 to 20, characterized in that said shift and delay means (220-1 - 220-n) includes an optical coupler (20-1) which optically couples said shift and delay means to a corresponding one of said first optical data buses (150-1 - 150-m).

Claim 24

The optical switching system as claimed in any of claims 14 to 21, characterized in that said input optical signal is made up of cells having a fixed length and a header which includes a routing information, said routing information comprising a number a of output optical fibers which are coupled to an output side of said fifth means, an optical frequency b and an output time slot c.

Claim 25

The optical switching system as claimed in claim 22, characterized in that said first shift means (360-1 - 360-n) converts the wavelengths of all the stored optical signals depending on values of the routing information (a, b, c).

Claim 26

The optical switching system as claimed in claim 23, characterized in that said first shift means (360-1 - 360-n) converts optical frequencies of all the stored optical signals to an optical frequency abc.

Claim 27

The optical switching system as claimed in any of claims 14 to 24, characterized in that said second shift means (510-1 - 510-n) includes a plurality of optical bandpass filters (50-1 - 50-5) having mutually different passbands coupled to said second optical data bus (410).

Claim 28

The optical switching system as claimed in any of claims 14 to 25, characterized in that said detecting means, said optical bandpass filters, said control information detecting means, said first shift means, said shift and delay means, said second shift means and said multiplexing means process optical signals by an all-optical processing.

Claim 29

The optical switching system as claimed in any of claims 14 to 26, characterized in that said control information contains at least an information selected from a group including a wavelength information of the optical input signal, a content information, a wavelength information of the optical output signal, an output channel information, an information quantity, a priority information, and a time slot information.